

A066491


Twin prime gaps: Pairs n, n+1 such that f(n) = f(n+1), where f is the prime gaps function given by f(m) = p(m+1)p(m) and p(m) denotes the mth prime.


0



2, 3, 15, 16, 36, 37, 39, 40, 46, 47, 54, 55, 55, 56, 73, 74, 102, 103, 107, 108, 110, 111, 118, 119, 129, 130, 160, 161, 164, 165, 184, 185, 187, 188, 194, 195, 199, 200, 218, 219, 239, 240, 271, 272, 272, 273, 291, 292, 339, 340, 358, 359, 387, 388, 419, 420
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OFFSET

1,1


COMMENTS

Each pair of a(n) yields a triple of primes in arithmetic progression, e.g. 2,3 yields the prime triple 3,5,7.


LINKS

Table of n, a(n) for n=1..56.


EXAMPLE

2,3 is a twin prime gap since f(2) = f(3) = 2. 54,55 is a twin prime gap since f(54) = f(55) = 6.


MATHEMATICA

(to find the smaller number in each twin prime gap) f[n_] := Prime[n + 1]  Prime[n]; Select[Range[1, 10^3], f[ # ] == f[ # + 1] &]


CROSSREFS

Sequence in context: A309765 A238691 A241721 * A282383 A299486 A173334
Adjacent sequences: A066488 A066489 A066490 * A066492 A066493 A066494


KEYWORD

easy,nonn


AUTHOR

Joseph L. Pe, Jan 03 2002


EXTENSIONS

More terms from Jason Earls, Jan 05 2002


STATUS

approved



