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A071920 Square array giving number of unimodal functions [n]->[m] for n>=0, m>=0, with a(0,m)=0 for all m>=0, read by antidiagonals. 1
0, 0, 0, 0, 1, 0, 0, 2, 1, 0, 0, 3, 4, 1, 0, 0, 4, 9, 7, 1, 0, 0, 5, 16, 22, 11, 1, 0, 0, 6, 25, 50, 46, 16, 1, 0, 0, 7, 36, 95, 130, 86, 22, 1, 0, 0, 8, 49, 161, 295, 296, 148, 29, 1, 0, 0, 9, 64, 252, 581, 791, 610, 239, 37, 1, 0 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,8

COMMENTS

If one uses a definition of unimodality that involves existential quantifiers on the domain of a function then a(0,m)=0 a priori.

FORMULA

a(n, m)=sum_{k=0}^{m-1} binomial(n+2k-1, 2k).

CROSSREFS

Sequence in context: A034365 A103778 A099423 * A065719 A204387 A113953

Adjacent sequences:  A071917 A071918 A071919 * A071921 A071922 A071923

KEYWORD

nonn,easy,tabl

AUTHOR

Michele Dondi (bik.mido(AT)tiscalinet.it), Jun 14, 2002

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Last modified February 17 09:30 EST 2012. Contains 206009 sequences.