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A091718
a(n) = Max{gcd(P(n),P(k)): 0<=k<n}, P = partition function.
2
1, 1, 1, 1, 1, 1, 5, 11, 15, 7, 14, 11, 1, 15, 22, 77, 33, 77, 35, 33, 99, 6, 5, 45, 22, 42, 70, 22, 55, 12, 22, 33, 69, 10, 363, 1, 77, 215, 385, 147, 231, 22, 891, 25, 41, 6, 98, 21, 55, 22, 363, 759, 63, 385, 71, 11, 6, 55, 220, 17, 1155, 286, 3, 781, 2, 53, 1, 245
OFFSET
1,7
LINKS
MAPLE
a:= n-> (p-> max(seq(igcd(p(n), p(k)), k=0..n-1)))(combinat[numbpart]):
seq(a(n), n=1..100); # Alois P. Heinz, Oct 26 2019
MATHEMATICA
m = 100; p = PartitionsP[Range[0, m]]; Table[Max[GCD[p[[n]], p[[1 ;; n - 1]]]], {n, 2, m + 1}] (* Amiram Eldar, May 10 2020 *)
PROG
(PARI) a(n) = my(pn=numbpart(n)); vecmax(vector(n, k, k--; gcd(pn, numbpart(k)))); \\ Michel Marcus, May 10 2020
CROSSREFS
Sequence in context: A079030 A103011 A137002 * A078002 A171418 A213444
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Feb 01 2004
STATUS
approved