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A036056
Sum of the lengths of the cycle types of the permutation created by length sorting on the partitions of n.
12
1, 1, 1, 3, 3, 7, 11, 20, 25, 37, 54, 74, 98, 131, 169, 227, 293, 380, 486, 622, 787, 970, 1251, 1569, 1946, 2431, 3003, 3713, 4544, 5599, 6831, 8324, 10139, 12305, 14873, 17974, 21632, 26006, 31180, 37334, 44575, 53171, 63257, 75172, 89132, 105523, 124749, 147268, 173520, 204222
OFFSET
1,4
PROG
(PARI)
OrderCycs(v)={my(t=vector(#v), L=List()); for(i=1, #v, my(c=0, j=i); while(!t[j], t[j]=1; j=v[j]; c++); if(c, listput(L, c))); Vec(L)}
a(n)={my(u=vecsort([Vecsmall(Vecrev(p)) | p<-partitions(n)])); my(v=vecsort(u, (x, y)->lex(#x, #y), 1+4)); vecsum(Set(OrderCycs(v)))} \\ Andrew Howroyd, Sep 17 2019
CROSSREFS
KEYWORD
nonn
EXTENSIONS
a(31)-a(50) from Andrew Howroyd, Sep 17 2019
STATUS
approved