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A092690 Row sums of triangle A092689, which is related to the central trinomial coefficients (A002426). 1
1, 2, 7, 22, 71, 226, 717, 2262, 7107, 22246, 69413, 215986, 670441, 2076686, 6420403, 19816362, 61070499, 187953174, 577742469, 1773918642, 5441141589, 16674016758, 51052484343, 156188410098, 477487110429, 1458741494826 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

PROG

(PARI) {T(n, k)=if(n<0|k>n, 0, if(n==0&k==0, 1, if(n==1&k<=1, 1, if(k==n-1, T(n-1, 0), if(k==n, T(n, 0), 2*T(n-1, k)+T(n-1, k+1))))))} a(n)=sum(k=0, n, T(n, k))

CROSSREFS

Cf. A002426, A092683, A092686, A092689.

Sequence in context: A077833 A106438 A109999 * A030186 A162770 A116387

Adjacent sequences:  A092687 A092688 A092689 * A092691 A092692 A092693

KEYWORD

nonn

AUTHOR

Paul D. Hanna (pauldhanna(AT)juno.com), Mar 04 2004

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Last modified February 14 15:32 EST 2012. Contains 205635 sequences.