A318285 Number of non-isomorphic multiset partitions of a multiset whose multiplicities are the prime indices of n.
1, 1, 2, 2, 3, 4, 5, 3, 7, 7, 7, 9, 11, 12, 16, 5, 15, 17, 22, 16, 29, 19, 30, 16, 21, 30, 23, 29, 42, 52, 56, 7, 47, 45, 57, 43, 77, 67, 77, 31, 101, 98, 135, 47, 85, 97, 176, 29, 66, 64, 118, 77, 231, 69, 97, 57, 181, 139, 297, 137, 385, 195, 166, 11, 162, 171, 490, 118
Offset: 1
Keywords
Examples
Non-isomorphic representatives of the a(12) = 9 multiset partitions of {1,1,2,3}: {{1,1,2,3}} {{1},{1,2,3}} {{2},{1,1,3}} {{1,1},{2,3}} {{1,2},{1,3}} {{1},{1},{2,3}} {{1},{2},{1,3}} {{2},{3},{1,1}} {{1},{1},{2},{3}}
Links
- Andrew Howroyd, Table of n, a(n) for n = 1..130
Crossrefs
Programs
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PARI
\\ See links in A339645 for combinatorial species functions. sig(n)={my(f=factor(n), sig=vector(primepi(vecmax(f[,1])))); for(i=1, #f~, sig[primepi(f[i,1])]=f[i,2]); sig} C(sig)={my(n=sum(i=1, #sig, i*sig[i]), A=Vec(symGroupSeries(n)-1), B=O(x*x^n), c=prod(i=1, #sig, if(sig[i], sApplyCI(A[sig[i]], sig[i], A[i], i), 1))); polcoef(OgfSeries(sCartProd(c*x^n + B, sExp(x*Ser(A) + B))), n)} a(n)={if(n==1, 1, C(sig(n)))} \\ Andrew Howroyd, Jan 17 2023
Extensions
Terms a(31) and beyond from Andrew Howroyd, Jan 17 2023