how to find # of OBS for the neighboring DV having exactly same value in the below data?

I mean for SUBJ # 1006 ID # 848 OBS# should be 61902 and 61904
           for SUBJ # 1005 ID # 847 OBS# should be 61714 61716 61718 61720

data = structure(list(OBS = c(61812L, 61814L, 61816L, 61818L, 61820L,
61822L, 61824L, 61826L, 61828L, 61830L, 61832L, 61834L, 61836L,
61838L, 61840L, 61842L, 61844L, 61846L, 61848L, 61850L, 61852L,
61854L, 61856L, 61858L, 61860L, 61862L, 61864L, 61866L, 61868L,
61870L, 61872L, 61874L, 61876L, 61878L, 61880L, 61882L, 61884L,
61886L, 61888L, 61890L, 61892L, 61894L, 61896L, 61898L, 61900L,
61902L, 61904L, 61906L, 61908L, 61714L, 61716L, 61718L, 61720L,
61722L, 61724L, 61726L, 61728L, 61730L, 61732L, 61734L, 61736L,
61738L, 61740L, 61742L, 61744L, 61746L, 61748L, 61750L, 61752L,
61754L, 61756L, 61758L, 61760L, 61762L, 61764L, 61766L, 61768L,
61770L, 61772L, 61774L, 61776L, 61778L, 61780L, 61782L, 61784L,
61786L, 61788L, 61790L, 61792L, 61794L, 61796L, 61798L, 61800L,
61802L, 61804L, 61806L, 61808L, 61810L), ID = c(848L, 848L, 848L,
848L, 848L, 848L, 848L, 848L, 848L, 848L, 848L, 848L, 848L, 848L,
848L, 848L, 848L, 848L, 848L, 848L, 848L, 848L, 848L, 848L, 848L,
848L, 848L, 848L, 848L, 848L, 848L, 848L, 848L, 848L, 848L, 848L,
848L, 848L, 848L, 848L, 848L, 848L, 848L, 848L, 848L, 848L, 848L,
848L, 848L, 847L, 847L, 847L, 847L, 847L, 847L, 847L, 847L, 847L,
847L, 847L, 847L, 847L, 847L, 847L, 847L, 847L, 847L, 847L, 847L,
847L, 847L, 847L, 847L, 847L, 847L, 847L, 847L, 847L, 847L, 847L,
847L, 847L, 847L, 847L, 847L, 847L, 847L, 847L, 847L, 847L, 847L,
847L, 847L, 847L, 847L, 847L, 847L, 847L), STDY = c(1203L, 1203L,
1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L,
1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L,
1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L,
1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L,
1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L,
1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L,
1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L,
1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L,
1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L,
1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L, 1203L,
1203L, 1203L, 1203L, 1203L, 1203L, 1203L), SUBJ = c(1006L, 1006L,
1006L, 1006L, 1006L, 1006L, 1006L, 1006L, 1006L, 1006L, 1006L,
1006L, 1006L, 1006L, 1006L, 1006L, 1006L, 1006L, 1006L, 1006L,
1006L, 1006L, 1006L, 1006L, 1006L, 1006L, 1006L, 1006L, 1006L,
1006L, 1006L, 1006L, 1006L, 1006L, 1006L, 1006L, 1006L, 1006L,
1006L, 1006L, 1006L, 1006L, 1006L, 1006L, 1006L, 1006L, 1006L,
1006L, 1006L, 1005L, 1005L, 1005L, 1005L, 1005L, 1005L, 1005L,
1005L, 1005L, 1005L, 1005L, 1005L, 1005L, 1005L, 1005L, 1005L,
1005L, 1005L, 1005L, 1005L, 1005L, 1005L, 1005L, 1005L, 1005L,
1005L, 1005L, 1005L, 1005L, 1005L, 1005L, 1005L, 1005L, 1005L,
1005L, 1005L, 1005L, 1005L, 1005L, 1005L, 1005L, 1005L, 1005L,
1005L, 1005L, 1005L, 1005L, 1005L, 1005L), DATE = structure(c(45L,
46L, 47L, 48L, 49L, 50L, 24L, 25L, 26L, 27L, 28L, 29L, 30L, 31L,
32L, 33L, 35L, 36L, 37L, 38L, 39L, 40L, 41L, 42L, 43L, 44L, 51L,
62L, 63L, 66L, 52L, 53L, 54L, 55L, 56L, 58L, 59L, 60L, 61L, 67L,
74L, 68L, 71L, 73L, 76L, 77L, 78L, 80L, 81L, 14L, 18L, 19L, 20L,
21L, 22L, 23L, 3L, 4L, 5L, 6L, 7L, 8L, 9L, 10L, 11L, 12L, 13L,
16L, 17L, 34L, 47L, 49L, 24L, 28L, 31L, 35L, 38L, 41L, 44L, 62L,
64L, 54L, 55L, 57L, 59L, 61L, 67L, 74L, 75L, 69L, 72L, 76L, 79L,
1L, 2L, 15L, 65L, 70L), .Label = c("10/27/2005", "12/8/2005",
"5/11/2005", "5/12/2005", "5/13/2005", "5/14/2005", "5/15/2005",
"5/17/2005", "5/18/2005", "5/19/2005", "5/23/2005", "5/25/2005",
"5/27/2005", "5/3/2005", "5/3/2006", "5/30/2005", "5/31/2005",
"5/4/2005", "5/5/2005", "5/6/2005", "5/7/2005", "5/8/2005", "5/9/2005",
"6/10/2005", "6/11/2005", "6/12/2005", "6/13/2005", "6/14/2005",
"6/15/2005", "6/16/2005", "6/17/2005", "6/18/2005", "6/19/2005",
"6/2/2005", "6/20/2005", "6/21/2005", "6/22/2005", "6/23/2005",
"6/24/2005", "6/26/2005", "6/27/2005", "6/28/2005", "6/29/2005",
"6/30/2005", "6/4/2005", "6/5/2005", "6/6/2005", "6/7/2005",
"6/8/2005", "6/9/2005", "7/1/2005", "7/11/2005", "7/13/2005",
"7/14/2005", "7/18/2005", "7/20/2005", "7/21/2005", "7/22/2005",
"7/25/2005", "7/27/2005", "7/28/2005", "7/4/2005", "7/6/2005",
"7/7/2005", "7/7/2006", "7/8/2005", "8/1/2005", "8/11/2005",
"8/15/2005", "8/17/2006", "8/18/2005", "8/22/2005", "8/25/2005",
"8/4/2005", "8/8/2005", "9/1/2005", "9/14/2005", "9/20/2005",
"9/22/2005", "9/24/2005", "9/26/2005"), class = "factor"), TIME = structure(c(1L,
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L,
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L,
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L,
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L,
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L,
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L,
1L), .Label = "8:00", class = "factor"), TSFD = c(12L, 36L, 60L,
84L, 108L, 132L, 156L, 180L, 204L, 228L, 252L, 276L, 300L, 324L,
348L, 372L, 396L, 420L, 444L, 468L, 492L, 540L, 564L, 588L, 612L,
636L, 660L, 732L, 780L, 828L, 900L, 948L, 972L, 1068L, 1116L,
1164L, 1236L, 1284L, 1308L, 1404L, 1476L, 1644L, 1812L, 1980L,
2148L, 2460L, 2604L, 2700L, 2748L, 12L, 36L, 60L, 84L, 108L,
132L, 156L, 204L, 228L, 252L, 276L, 300L, 348L, 372L, 396L, 492L,
540L, 588L, 660L, 684L, 732L, 828L, 876L, 924L, 1020L, 1092L,
1164L, 1236L, 1332L, 1404L, 1500L, 1572L, 1740L, 1836L, 1908L,
2004L, 2076L, 2172L, 2244L, 2340L, 2508L, 2676L, 2916L, 3420L,
4260L, 5268L, 8772L, 10332L, 11316L), TSLD = c(12L, 12L, 12L,
12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L,
12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L,
12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L,
12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L,
12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L,
12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L,
12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L, 12L,
12L, 12L, 12L, 12L), NOMTIME = c(24L, 24L, 24L, 24L, 24L, 24L,
24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L,
24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L,
24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L,
24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L,
24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L,
24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L,
24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L, 24L,
24L), DV = c(14, 18.7, 15.8, 15.1, 13.2, 14.9, 20.2, 17.7, 14.6,
13.4, 12.3, 11.6, 10.7, 14.6, 15.5, 13.7, 14.2, 15.3, 18.4, 17,
18.2, 18.5, 22.8, 25.6, 15.8, 14.5, 18.6, 13.6, 16.8, 13.3, 14,
14.5, 26.7, 13.4, 18.5, 15.5, 13.9, 14.4, 17, 11.6, 9.2, 11.4,
9.6, 11.8, 8.8, 9.2, 9.2, 8.4, 7.6, 30, 30, 30, 30, 19.6, 23.6,
10.7, 9.1, 10.3, 8.9, 10.4, 9.5, 11.6, 11, 9.9, 10.6, 11.4, 18.6,
16, 12.7, 12.8, 9.3, 8.8, 11.1, 8.6, 9.7, 10.8, 10.7, 6.9, 8.3,
9.8, 8.1, 7, 6.1, 4.8, 7.5, 6, 10.6, 7.6, 5.5, 7.3, 7, 7.2, 8.5,
9.5, 6.2, 8.7, 10.1, 11.4)), .Names = c("OBS", "ID", "STDY",
"SUBJ", "DATE", "TIME", "TSFD", "TSLD", "NOMTIME", "DV"), class = "data.frame", row.names = c(NA,
-98L))