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 A305552 #13 Sep 07 2018 12:03:38 %S A305552 1,1,3,5,12,17,47,65,170,277,655,1025,2739,4097,10281,17257,41364, %T A305552 65537,170047,262145,660296,1094457,2621965,4194305,10898799,16792721, %U A305552 41945103,69938141,168546184,268435457,694029255,1073741825,2696094037,4474449261,10737451027 %N A305552 Number of uniform normal multiset partitions of weight n. %C A305552 A multiset is normal if it spans an initial interval of positive integers. A multiset partition m is uniform if all parts have the same size, and normal if all parts are normal. The weight of m is the sum of sizes of its parts. %H A305552 Andrew Howroyd, <a href="/A305552/b305552.txt">Table of n, a(n) for n = 0..1000</a> %F A305552 a(n) = Sum_{d|n} binomial(2^(n/d - 1) + d - 1, d). %e A305552 The a(4) = 12 uniform normal multiset partitions: %e A305552 {1111}, {1222}, {1122}, {1112}, {1233}, {1223}, {1123}, {1234}, %e A305552 {11,11}, {11,12}, {12,12}, %e A305552 {1,1,1,1}. %t A305552 Table[Sum[Binomial[2^(n/k-1)+k-1,k],{k,Divisors[n]}],{n,35}] %o A305552 (PARI) a(n)={if(n<1, n==0, sumdiv(n, d, binomial(2^(n/d - 1) + d - 1, d)))} \\ _Andrew Howroyd_, Jun 22 2018 %Y A305552 Cf. A000005, A001315, A007716, A034691, A038041, A074854, A289078, A305552, A306017. %K A305552 nonn %O A305552 0,3 %A A305552 _Gus Wiseman_, Jun 20 2018