OFFSET
1,2
LINKS
Andrew Howroyd, Table of n, a(n) for n = 1..200
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
KEYWORD
nonn
AUTHOR
Gary W. Adamson, Feb 18 2008
EXTENSIONS
Terms a(12) and beyond from Andrew Howroyd, Aug 09 2018
STATUS
approved