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Centered square numbers that are prime powers of the form (4n+1)^k.
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%I #5 Sep 16 2015 14:03:03

%S 5,13,25,41,61,113,181,313,421,613,761,841,1013,1201,1301,1741,1861,

%T 2113,2381,2521,3121,3613,4513,5101,7321,8581,9661,9941,10513,12641,

%U 13613,14281,14621,15313,16381,19013,19801,20201,21013,21841,23981

%N Centered square numbers that are prime powers of the form (4n+1)^k.

%t a = {}; For[i = 1, i < 140, i++, k = 1; b = (2*i*(i + 1) + 1); While[b^(1/k) > 4, If[PrimeQ[b^(1/k)], If[Mod[b^(1/k), 4] == 1, AppendTo[a, b]]]; k++ ]]; a (* _Stefan Steinerberger_, Oct 21 2007 *)

%Y Subsequence of A001844 and A120960.

%K nonn

%O 1,1

%A _Mats Granvik_, Oct 18 2007, Oct 19 2007

%E More terms from _Stefan Steinerberger_, Oct 21 2007