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 A301762 #5 Mar 26 2018 20:03:17 %S A301762 1,1,2,4,7,12,21,34,55,90,143,220,347,528,805,1226,1831,2719,4048, %T A301762 5940,8710,12714,18403,26529,38220,54679,77899,110810,156848,221181, %U A301762 311635,436705,610597,852125,1184928,1644136,2276551,3142523,4328960,5953523,8167209 %N A301762 Number of ways to choose a constant rooted partition of each part in a rooted partition of n. %C A301762 A rooted partition of n is an integer partition of n - 1. %F A301762 O.g.f.: Product_{n>0} 1/(1 - d(n-1) x^n) where d(n) = A000005(n) and d(0) = 1. %e A301762 The a(5) = 7 rooted twice-partitions where the latter rooted partitions are constant: (3), (111), (2)(), (11)(), (1)(1), (1)()(), ()()()(). %t A301762 Table[Sum[Product[If[k===1,1,DivisorSigma[0,k-1]],{k,ptn}],{ptn,IntegerPartitions[n-1]}],{n,20}] %Y A301762 Cf. A002865, A063834, A093637, A279784, A295935, A300383, A301422, A301462, A301467, A301480, A301706. %K A301762 nonn %O A301762 1,3 %A A301762 _Gus Wiseman_, Mar 26 2018