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 A354088 #8 May 17 2022 17:50:05 %S A354088 1,1,2,5,7,2,1,3,31,7,2,10,4,1,14,121,6,31,3,35,2,2,2,6,106,4,10,5,19, %T A354088 14,1,35,4,6,7,155,14,3,8,21,8,2,11,10,217,2,2,242,38,106,12,20,31,10, %U A354088 14,3,6,19,6,70,29,1,31,1069,28,4,13,30,4,7,4,93,12,14,212,15,2,8,3,847,781,8,14,10,42,11,38 %N A354088 Sum of divisors function conjugated by Pythagorean prime shift: a(n) = A348747(sigma(A348746(n))). %C A354088 This is variant of A326042, and like that sequence, also this one is multiplicative. %H A354088 <a href="/index/Pri#prime_indices">Index entries for sequences computed from indices in prime factorization</a> %H A354088 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a> %F A354088 Multiplicative with a(p^e) = A348747((q^(e+1)-1)/(q-1)), where q = A348744(A000720(p)). %F A354088 a(n) = A348747(A354089(n)) = A348747(A000203(A348746(n))). %o A354088 (PARI) %o A354088 A348746(n) = { my(f=factor(n)); for(k=1,#f~, if(2==f[k,1], f[k,1]=3, if(3==f[k,1], f[k,1]=5, if(1==(f[k,1]%4), for(i=1+primepi(f[k,1]),oo,if(1==(prime(i)%4), f[k,1]=prime(i); break)))))); factorback(f); }; %o A354088 A348747(n) = { my(f=factor(n)); for(k=1,#f~, if(f[k,1]<=3, f[k,1]--, if(5==f[k,1], f[k,1]=3, if(1==(f[k,1]%4), forstep(i=primepi(f[k,1])-1,0,-1,if(1==(prime(i)%4), f[k,1]=prime(i); break)))))); factorback(f); }; %o A354088 A354088(n) = A348747(sigma(A348746(n))); %Y A354088 Cf. A000203, A326042, A348744, A348746, A348747, A354089. %Y A354088 Cf. also A326042, A354096 for variants. %K A354088 nonn,mult %O A354088 1,3 %A A354088 _Antti Karttunen_, May 17 2022