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 A246270 #13 Mar 08 2025 18:38:22
%S A246270 0,1,0,2,1,1,1,3,0,2,0,2,0,2,1,4,1,1,1,3,1,1,0,3,2,1,0,3,1,2,0,5,0,2,
%T A246270 2,2,0,2,0,4,1,2,1,2,1,1,0,4,2,3,1,2,1,1,1,4,1,2,0,3,1,1,1,6,1,1,1,3,
%U A246270 0,3,0,3,1,1,2,3,1,1,1,5,0,2,0,3,2,2,1,3,0,2,1,2,0,1,2,5
%N A246270 Number of prime factors of the form 4k+3 (counted with multiplicity) in A003961(n): a(n) = A065339(A003961(n)).
%H A246270 Antti Karttunen, <a href="/A246270/b246270.txt">Table of n, a(n) for n = 1..10080</a>
%F A246270 a(n) = A065339(A003961(n)).
%F A246270 a(n) = A001222(A246269(n)).
%F A246270 a(n) = A007949(A246269(n)).
%F A246270 Other identities.
%F A246270 If n = u*v, a(n) = a(u)+a(v).
%F A246270 For all n >= 0, a(2^n) = n.
%o A246270 (PARI)
%o A246270 default(primelimit, 2^22)
%o A246270 A246269(n) = my(f = factor(n)); for (i=1, #f~, f[i, 1] = (nextprime(f[i, 1]+1)%4)); factorback(f);
%o A246270 A246270(n) = bigomega(A246269(n));
%o A246270 for(n=1, 10080, write("b246270.txt", n, " ", A246270(n)));
%o A246270 (Scheme)
%o A246270 (define (A246270 n) (A065339 (A003961 n)))
%o A246270 (Scheme)
%o A246270 (define (A246270 n) (A007949 (A246269 n)))
%Y A246270 Cf. A001222, A003961, A007949, A065339, A246269, A246272.
%K A246270 nonn
%O A246270 1,4
%A A246270 _Antti Karttunen_, Aug 21 2014