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Primes p such that tau(p-1)+tau(p+1) is larger than for any previous term. (Smallest prime sandwiched between more composite numbers.)
8

%I #10 Jul 19 2015 01:28:41

%S 2,3,5,7,11,17,19,29,41,71,179,181,239,419,701,839,881,1259,1871,2161,

%T 2521,4159,5039,7561,10079,13441,13859,20161,22679,30241,35281,45361,

%U 55439,65519,110879,138599,151201,166319,226799,262079,327599,332641

%N Primes p such that tau(p-1)+tau(p+1) is larger than for any previous term. (Smallest prime sandwiched between more composite numbers.)

%H Donovan Johnson, <a href="/A090481/b090481.txt">Table of n, a(n) for n = 1..100</a>

%e 17 follows 11 and 13 is not a term as tau(10) + tau(12) = tau(12) + tau(14) = 10.

%t a = {}; t = 0; Do[p = Prime[n]; s = DivisorSigma[0, p - 1] + DivisorSigma[0, p + 1]; If[s > t, t = s; AppendTo[a, p]], {n, 1, 10^5}]; a (* _Robert G. Wilson v_, Dec 04 2003 *)

%Y Cf. A090482, A000005.

%K nonn

%O 1,1

%A _Amarnath Murthy_, Dec 02 2003

%E More terms from _Robert G. Wilson v_, Dec 04 2003