A260517 - OEIS

%I #23 Aug 29 2015 00:47:03

%S 51,105,144,165,234,255,276,630,1041,2289,2325,2466,4251,5460,9006,

%T 9699,10380,10479,12006,13701,14166,15690,18090,19425,20190,20295,

%U 21540,26706,26796,32487,32871,33684,33789,35520,37455,38661,41685,42771,46515,47760

%N Numbers equidistant from twin prime pairs that are also equidistant from numbers equidistant from twin prime pairs.

%H Robert G. Wilson v, <a href="/A260517/b260517.txt">Table of n, a(n) for n = 1..1257</a>

%e 165 is a term because it is equidistant from 144 and 186. 144 and 186 are both equidistant from twin primes, according to A074953.

%t t = Select[ Prime@ Range@ 5000, PrimeQ[# + 2] &]; d = Differences@ t; (t[[#+1]] + t[[#+2]]& /@ Select[ Range[ Length[d] - 2], d[[#]] == d[[#+2]] &])/2 + 1 (* _Robert G. Wilson v_, Jul 29 2015 *)

%Y Cf. A001097 (Twin primes), A074953 (Numbers equidistant from twin prime pairs).

%K nonn

%O 1,1

%A _Peter Woodward_, Jul 27 2015