%I #40 Feb 16 2022 04:15:28
%S 1,4,7,10,16,19,22,31,34,37,40,49,52,55,64,70,76,79,82,91,97,100,106,
%T 112,115,121,136,139,142,154,157,166,169,175,184,187,190,199,205,211,
%U 217,220,229,232,244,250,262,271,274,286,289,301,304,307,310,316,322,331,337,346
%N Indices m for which A177961(m) - m = 1.
%C 1 is the smallest value of |A177961(m) - m|.
%H Robert Israel, <a href="/A177965/b177965.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = (A002476(n-1) + 1)/2, n > 1.
%p 1,op(map(t -> 3*t+1, select(t -> isprime(6*t+1),[$1..1000]))); # _Robert Israel_, Jul 31 2015
%t Position[Table[If[m == 1, 2, Mean[{FactorInteger[2 m - 1][[1, 1]], FactorInteger[2 m + 1][[1, 1]]}]] - m, {m, 346}], n_ /; n == 1] // Flatten (* _Michael De Vlieger_, Aug 02 2015 *)
%Y Cf. A002476, A177961, A177964, A177966.
%K nonn
%O 1,2
%A _Vladimir Shevelev_, May 16 2010
%E More terms from _R. J. Mathar_, Oct 25 2010