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 A326568 #12 Jan 28 2025 20:51:54
%S A326568 1,1,1,1,2,1,1,1,1,1,3,1,2,2,1,1,3,1,3,1,1,1,4,1,2,1,1,1,1,1,1,2,1,2,
%T A326568 2,1,2,1,2,1,3,1,3,3,1,1,5,1,3,2,3,1,4,1,4,1,2,1,4,1,1,3,1,2,3,1,1,2,
%U A326568 3,1,5,1,2,3,3,2,1,1,5,1,1,1,1,1,2,1,1,1,1,1,3,2,1,2,6,1,1,1,1,1,3,1,4,1,2,1,5
%N A326568 Denominator of the average of the multiset of prime indices of n.
%C A326568 A prime index of n is a number m such that prime(m) divides n. The multiset of prime indices of n is row n of A112798.
%H A326568 Antti Karttunen, <a href="/A326568/b326568.txt">Table of n, a(n) for n = 2..65537</a>
%H A326568 <a href="/index/Pri#prime_indices">Index entries for sequences related to prime indices in the factorization of n</a>.
%e A326568 The prime indices of 12 are {1,1,2}, with average 4/3, so a(12) = 3.
%t A326568 Table[Denominator[Sum[q[[2]]*PrimePi[q[[1]]],{q,FactorInteger[n]}]/PrimeOmega[n]],{n,2,100}]
%o A326568 (PARI) A326568(n) = { my(f=factor(n)); denominator(sum(i=1,#f~,f[i,2]*primepi(f[i,1]))/bigomega(n)); }; \\ _Antti Karttunen_, Jan 28 2025
%Y A326568 a(n) is a divisor of Omega(n) = A001222(n).
%Y A326568 Positions of 1's are A316413.
%Y A326568 Cf. A001414, A056239, A067629, A112798, A123528/A123529, A289508, A289509, A290103, A316428, A326567, A326620.
%K A326568 nonn,frac
%O A326568 2,5
%A A326568 _Gus Wiseman_, Jul 13 2019
%E A326568 Starting offset corrected from 0 to 2 and data section extended to a(108) by _Antti Karttunen_, Jan 28 2025