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A143420
Row sums of triangle A373101.
1
1, 8, 55, 370, 2520, 17472, 123151, 880070, 6360706, 46402312, 341153384, 2524722928, 18789734496, 140521154048, 1055383259791, 7956220907758, 60179579570382, 456545145078408, 3472804505717170
OFFSET
2,2
COMMENTS
Each term in the sequence is a sum of tetrahedral numbers.
The underlying triangle mentioned as A143419 was lost and is now restored in A373101. - Georg Fischer, May 23 2024
EXAMPLE
a(5) = 370 = (20 + 165 + 165 + 20) = C(6,3) + C(11,3) + C(11,8) + C(6,3).
MAPLE
seq(add((binomial(n, k)^3 - binomial(n, k))/6, k=1..n-1), n=2..20); # Georg Fischer, May 23 2024
CROSSREFS
Cf. A108958 (row sums of A143418), A373101.
Sequence in context: A110184 A013698 A154245 * A075734 A033890 A010924
KEYWORD
nonn,easy
AUTHOR
Gary W. Adamson, Aug 14 2008
EXTENSIONS
Definition changed, a(7) corrected and more terms from Georg Fischer, May 23 2024
STATUS
approved