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 A307408 #16 Nov 17 2019 14:51:19
%S A307408 2,2,2,3,2,4,2,4,3,4,2,6,2,4,4,5,2,6,2,6,4,4,2,8,3,4,4,6,2,8,2,6,4,4,
%T A307408 4,8,2,4,4,8,2,8,2,6,6,4,2,10,3,6,4,6,2,8,4,8,4,4,2,11,2,4,6,7,4,8,2,
%U A307408 6,4,8,2,10,2,4,6,6,4,8,2,10,5,4,2,11,4,4,4,8,2,11,4,6,4,4,4,12,2,6,6,8,2,8,2,8
%N A307408 a(n) = (A001222(n) - 1)*A001221(n) + 2.
%C A307408 a(n) appears to differ from A000005 at n = 1 and when n is a term of A320632. Verified up to n=3000.
%C A307408 See also _Charlie Neder_'s May 14 2019 comment in A307409.
%H A307408 Antti Karttunen, <a href="/A307408/b307408.txt">Table of n, a(n) for n = 1..13440</a>
%H A307408 Antti Karttunen, <a href="/A307408/a307408.txt">Data supplement: n, a(n) computed for n = 1..100000</a>
%H A307408 <a href="/index/Eu#epf">Index entries for sequences computed from exponents in factorization of n</a>
%F A307408 a(n) = (A001222(n) - 1)*A001221(n) + 2.
%F A307408 a(n) = binomial(A001222(n) - 1, 1)*binomial(A001221(n), 1) + 2.
%F A307408 a(n) = A307409(n) + 2.
%t A307408 a[n_] := (PrimeOmega[n] - 1)*PrimeNu[n] + 2;
%t A307408 Table[a[n], {n, 1, 104}]
%o A307408 (PARI) A307408(n) = 2+((bigomega(n)-1)*omega(n)); \\ _Antti Karttunen_, Nov 17 2019
%Y A307408 Two more than A307409.
%Y A307408 Cf. A001221, A001222, A000005, A320632.
%K A307408 nonn
%O A307408 1,1
%A A307408 _Mats Granvik_, Apr 07 2019