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A321774
Number of compositions of n into parts with distinct multiplicities and with exactly four parts.
2
1, 4, 4, 8, 5, 8, 12, 12, 9, 16, 16, 16, 17, 20, 20, 24, 21, 24, 28, 28, 25, 32, 32, 32, 33, 36, 36, 40, 37, 40, 44, 44, 41, 48, 48, 48, 49, 52, 52, 56, 53, 56, 60, 60, 57, 64, 64, 64, 65, 68, 68, 72, 69, 72, 76, 76, 73, 80, 80, 80, 81, 84, 84, 88, 85, 88, 92
OFFSET
4,2
LINKS
FORMULA
Conjectures from Colin Barker, Dec 11 2018: (Start)
G.f.: x^4*(1 + 4*x + 4*x^2 + 7*x^3) / ((1 - x)^2*(1 + x)*(1 + x^2)*(1 + x + x^2)).
a(n) = a(n-3) + a(n-4) - a(n-7) for n>10.
(End)
CROSSREFS
Column k=4 of A242887.
Sequence in context: A339756 A163369 A290841 * A254267 A028266 A275982
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Nov 18 2018
STATUS
approved