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A307614
Number of partitions of the n-th triangular number into consecutive positive triangular numbers.
5
1, 1, 1, 2, 1, 1, 1, 2, 1, 2, 1, 1, 1, 1, 2, 2, 1, 1, 1, 2, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 1, 2, 1, 1, 2, 2, 1, 1, 1, 2, 1, 2, 1, 1, 2, 2, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 1, 1, 1, 2, 1
OFFSET
1,4
FORMULA
a(n) = [x^(n*(n+1)/2)] Sum_{i>=1} Sum_{j>=i} Product_{k=i..j} x^(k*(k+1)/2).
EXAMPLE
A000217(4) = 10 = 1 + 3 + 6, so a(4) = 2.
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Apr 18 2019
STATUS
approved