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%I #15 Sep 08 2022 08:46:17
%S 1,40401,62001,96721,121801,192721,326041,410881,555025,660969,683929,
%T 772641,786769,822649,1343281,1390041,1530169,1739761,1885129,1923769,
%U 1962801,2283121,2544025,2913849,3207681,3214849,3352561,3396649,3613801,3775249,3853369,4060225
%N Odd squares not of the form p + 2^k with p prime.
%C The sequence contains also Sierpiński numbers (i.e., 4521731193704761, 60428287050225649).
%H Robert Israel, <a href="/A276567/b276567.txt">Table of n, a(n) for n = 1..10000</a>
%F A006285 INTERSECT A016754.
%p filter:= proc(n) local k;
%p for k from 0 to ilog2(n) do
%p if isprime(n - 2^k) then return false fi
%p od:
%p true
%p end proc:
%p select(filter, [seq((2*i+1)^2, i=0..10^4)]); # _Robert Israel_, Sep 07 2016
%t filterQ[n_] := Module[{k}, For[k = 0, k <= Log[2, n], k++, If[PrimeQ[n - 2^k], Return[False]]]; True];
%t Select[Table[(2i+1)^2, {i, 0, 10^4}], filterQ] (* _Jean-François Alcover_, Oct 06 2020, after Maple *)
%o (Magma) lst:=[]; for s in [1..2015 by 2] do n:=s^2; x:=0; repeat x+:=1; a:=n-2^x; until a lt 1 or IsPrime(a); if a lt 1 then Append(~lst, n); end if; end for; lst;
%Y Cf. A006285, A016754.
%K nonn
%O 1,2
%A _Arkadiusz Wesolowski_, Sep 06 2016
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