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A104880
Diagonal sums of a sum-of-powers triangle.
1
1, 1, 2, 3, 5, 8, 14, 26, 53, 117, 280, 721, 1989, 5844, 18188, 59652, 205305, 739041, 2775190, 10846975, 44039765, 185391480, 807776210, 3637193486, 16900721837, 80939650565, 399061251260, 2023408865997, 10540656630133, 56362743769012
OFFSET
0,3
COMMENTS
Diagonal sums of A104878.
FORMULA
a(0)=1, a(1)=1, a(n)=n+sum{k=2..floor(n/2), (k^(n-2k+1)-1)/(k-1)}, n>1.
CROSSREFS
Sequence in context: A212657 A065955 A196118 * A152478 A102973 A371992
KEYWORD
easy,nonn
AUTHOR
Paul Barry, Mar 28 2005
STATUS
approved