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 A114422 Riordan array (1/sqrt(1-2x-3x^2), M(x)-1) where M(x) is the g.f. of the Motzkin numbers A001006. 14
 1, 1, 1, 3, 3, 1, 7, 9, 5, 1, 19, 26, 19, 7, 1, 51, 75, 65, 33, 9, 1, 141, 216, 211, 132, 51, 11, 1, 393, 623, 665, 483, 235, 73, 13, 1, 1107, 1800, 2058, 1674, 963, 382, 99, 15, 1, 3139, 5211, 6294, 5598, 3663, 1739, 581, 129, 17, 1, 8953, 15115, 19095, 18261, 13243 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,4 COMMENTS First column is central trinomial numbers A002426. Second column is A005774. Third column is A025568. Row sums are A116387. Diagonal sums are A116388. Product of A007318 and A116382. Column k has e.g.f. exp(x)*sum{j=0..k, C(k,j)*Bessel_I(k+j,2x)}. LINKS FORMULA Riordan array (1/sqrt(1-2x-3x^2), (1-x-2x^2-sqrt(1-2x-3x^2))/(2x^2)); Number triangle T(n,k)=sum{j=0..n, C(n,j-k)C(j,n-j)}. EXAMPLE Triangle begins 1, 1, 1, 3, 3, 1, 7, 9, 5, 1, 19, 26, 19, 7, 1, 51, 75, 65, 33, 9, 1, 141, 216, 211, 132, 51, 11, 1 CROSSREFS Sequence in context: A180735 A116401 A106479 * A127501 A181304 A118408 Adjacent sequences:  A114419 A114420 A114421 * A114423 A114424 A114425 KEYWORD easy,nonn,tabl AUTHOR Paul Barry, Feb 12 2006 STATUS approved

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