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 A343569 #8 Apr 20 2021 10:10:31 %S A343569 1,6,8,10,12,48,16,18,20,72,24,80,28,96,96,34,36,120,40,120,128,144, %T A343569 48,144,52,168,56,160,60,576,64,66,192,216,192,200,76,240,224,216,84, %U A343569 768,88,240,240,288,96,272,100,312,288,280,108,336,288,288,320,360,120,960,124,384,320,130 %N A343569 If n = Product (p_j^k_j) then a(n) = Product (2*(p_j^k_j + 1)), with a(1) = 1. %F A343569 a(n) = usigma(n) * 2^omega(n). %F A343569 a(n) = Sum_{d|n, gcd(d, n/d) = 1} usigma(d) * usigma(n/d). %F A343569 a(n) = Sum_{d|n, gcd(d, n/d) = 1} d * 2^omega(d) * 2^omega(n/d). %F A343569 a(n) = Sum_{d|n, gcd(d, n/d) = 1} A343525(d). %t A343569 a[1] = 1; a[n_] := Times @@ (2 (#[[1]]^#[[2]] + 1) & /@ FactorInteger[n]); Table[a[n], {n, 64}] %o A343569 (PARI) a(n) = my(f=factor(n)); for (k=1, #f~, f[k,1] = 2*f[k,1]^f[k,2] + 2; f[k,2] = 1); factorback(f); \\ _Michel Marcus_, Apr 20 2021 %Y A343569 Cf. A001221, A034444, A034448, A034761, A064840, A107759, A333557, A343525. %K A343569 nonn,mult %O A343569 1,2 %A A343569 _Ilya Gutkovskiy_, Apr 20 2021