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A137856
Row sums of triangle A137855.
2
1, 2, 4, 8, 17, 39, 97, 261, 756, 2343, 7722, 26917, 98789, 380360, 1531698, 6434385, 28130890, 127729730, 601196428, 2928369917, 14738842361, 76547694741, 409718539681, 2257459567236, 12789959138943, 74439150889080, 444647798089245, 2723583835351855
OFFSET
1,2
LINKS
FORMULA
a(n) = Sum_{k=1..n} Sum_{j=1..n-k+1} Stirling2(k, j). - Andrew Howroyd, Aug 09 2018
EXAMPLE
a(5) = 17 = sum of row 5 terms of triangle A137855: (1 + 2 + 5 + 8 + 1).
PROG
(PARI) a(n)={sum(k=1, n, sum(j=1, n-k+1, stirling(k, j, 2)))} \\ Andrew Howroyd, Aug 09 2018
CROSSREFS
Cf. A137855.
Partial sums of A024427.
Sequence in context: A054199 A054197 A287776 * A373353 A304970 A090375
KEYWORD
nonn
AUTHOR
Gary W. Adamson, Feb 18 2008
EXTENSIONS
Terms a(12) and beyond from Andrew Howroyd, Aug 09 2018
STATUS
approved