A320810 Number of non-isomorphic multiset partitions of weight n whose part-sizes have a common divisor > 1.
0, 2, 3, 12, 7, 84, 15, 410, 354, 3073, 56, 28300, 101, 210036, 126839, 2070047, 297, 25295952, 490, 269662769, 89071291, 3449056162, 1255, 51132696310, 400625539, 713071048480, 145126661415, 11351097702297, 4565, 199926713003444, 6842, 3460838122540969
Offset: 1
Keywords
Examples
Non-isomorphic representatives of the a(2) = 1 through a(5) = 7 multiset partitions whose part-sizes have a common divisor: {{1,1}} {{1,1,1}} {{1,1,1,1}} {{1,1,1,1,1}} {{1,2}} {{1,2,2}} {{1,1,2,2}} {{1,1,2,2,2}} {{1,2,3}} {{1,2,2,2}} {{1,2,2,2,2}} {{1,2,3,3}} {{1,2,2,3,3}} {{1,2,3,4}} {{1,2,3,3,3}} {{1,1},{1,1}} {{1,2,3,4,4}} {{1,1},{2,2}} {{1,2,3,4,5}} {{1,2},{1,2}} {{1,2},{2,2}} {{1,2},{3,3}} {{1,2},{3,4}} {{1,3},{2,3}} Non-isomorphic representatives of the a(2) = 1 through a(5) = 7 multiset partitions with periodic multiset union: {{1,1}} {{1,1,1}} {{1,1,1,1}} {{1,1,1,1,1}} {{1},{1}} {{1},{1,1}} {{1,1,2,2}} {{1},{1,1,1,1}} {{1},{1},{1}} {{1},{1,1,1}} {{1,1},{1,1,1}} {{1,1},{1,1}} {{1},{1},{1,1,1}} {{1},{1,2,2}} {{1},{1,1},{1,1}} {{1,1},{2,2}} {{1},{1},{1},{1,1}} {{1,2},{1,2}} {{1},{1},{1},{1},{1}} {{1},{1},{1,1}} {{1},{1},{2,2}} {{1},{2},{1,2}} {{1},{1},{1},{1}} {{1},{1},{2},{2}}
Links
- Andrew Howroyd, Table of n, a(n) for n = 1..50
Crossrefs
Programs
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PARI
\\ See links in A339645 for combinatorial species functions. seq(n)={my(A=symGroupSeries(n));Vec(OgfSeries(sCartProd(sExp(A), -sum(d=2, n, moebius(d) * (-1 + sExp(O(x*x^n) + sum(i=1, n\d, polcoef(A,i*d)*x^(i*d)))) ))), -n)} \\ Andrew Howroyd, Jan 17 2023
Formula
Extensions
Terms a(11) and beyond from Andrew Howroyd, Jan 17 2023
Comments