This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A292762 #26 Nov 23 2024 08:28:46
%S A292762 3,6,7,11,14,19,22,23,27,31,38,43,46,47,54,59,62,67,71,79,83,86,94,
%T A292762 103,107,118,127,131,134,139,142,151,158,163,166,167,179,191,199,206,
%U A292762 211,214,223,227,239,243,251,254,262,263,271,278,283,302,307,311,326,331,334,343,347,358,359,367,379,382
%N A292762 Numbers of the form p^k or 2*p^k, where p is a prime == 3 mod 4 and k is odd.
%C A292762 Numbers m such that sigma(m) == 0 mod 4 and phi(m) == 2 mod 4.
%H A292762 David A. Corneth, <a href="/A292762/b292762.txt">Table of n, a(n) for n = 1..13839</a> (Terms up to 200000)
%F A292762 As 22 = 2 * 11^1, which is of the form 2 * p^k with p = 11 = 2 * 4 + 3 == 3 mod 4 and k = 1 which is odd, 22 is a term. - _David A. Corneth_, Oct 02 2017
%t A292762 Do[If[Mod[DivisorSigma[1,n],4]==0 && Mod[EulerPhi[n],4]==2,Print[n]],{n,1,10^3}] (* _Vincenzo Librandi_, Oct 02 2017 *)
%o A292762 (PARI) isok(m) = ((sigma(m) % 4) == 0) && ((eulerphi(m) % 4) == 2); \\ _Michel Marcus_, Oct 02 2017
%o A292762 (PARI) upto(n) = {my(l=List()); forprime(p=3, n, if(p%4==3, forstep(e=1, logint(n,p), 2, listput(l,p^e); if(2*p^e <= n, listput(l,2*p^e))))); listsort(l); l} \\ _David A. Corneth_, Oct 02 2017
%Y A292762 Intersection of A097987 and A248150.
%Y A292762 Cf. A000010, A000203.
%K A292762 nonn
%O A292762 1,1
%A A292762 _N. J. A. Sloane_, Sep 26 2017