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 A379028 #8 Dec 16 2024 02:17:49
%S A379028 1,2,2,2,2,4,2,3,2,4,2,4,2,4,4,2,2,4,2,4,4,4,2,6,2,4,3,4,2,8,2,4,4,4,
%T A379028 4,4,2,4,4,6,2,8,2,4,4,4,2,4,2,4,4,4,2,6,4,6,4,4,2,8,2,4,4,2,4,8,2,4,
%U A379028 4,8,2,6,2,4,4,4,4,8,2,4,2,4,2,8,4,4,4
%N A379028 The number of modified exponential divisors of n.
%C A379028 If the prime factorization of n is Product_{i} p_i^e_i, then the modified exponential divisors of n are all the divisors of n that are of the form Product_{i} p_i^b_i such that 1 + b_i | 1 + e_i for all i.
%C A379028 The sum of these divisors is A241405(n).
%H A379028 Amiram Eldar, <a href="/A379028/b379028.txt">Table of n, a(n) for n = 1..10000</a>
%F A379028 Multiplicative with a(p^e) = d(e+1), where d(k) is the number of divisors of k (A000005).
%t A379028 f[p_, e_] := DivisorSigma[0, e + 1]; a[1] = 1; a[n_] := Times @@ f @@@ FactorInteger[n]; Array[a, 100]
%o A379028 (PARI) a(n) = vecprod(apply(x -> numdiv(x+1), factor(n)[, 2]));
%Y A379028 Row lengths of A379027.
%Y A379028 Cf. A241405.
%Y A379028 Similar sequences: A000005 (all divisors), A049419 (exponential), A037445 (infinitary), A034444 (unitary), A286324 (bi-unitary).
%K A379028 nonn,easy,mult
%O A379028 1,2
%A A379028 _Amiram Eldar_, Dec 14 2024