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A116382 Riordan array (1/sqrt(1-4x^2),(1-2x^2*c(x^2))(x^2*c(x^2))/(x(1-x-x^2*c(x^2))) where c(x) is the g.f. of A000108. 13
1, 0, 1, 2, 1, 1, 0, 3, 2, 1, 6, 4, 5, 3, 1, 0, 10, 10, 8, 4, 1, 20, 15, 21, 19, 12, 5, 1, 0, 35, 42, 42, 32, 17, 6, 1, 70, 56, 84, 92, 77, 50, 23, 7, 1, 0, 126, 168, 192, 180, 131, 74, 30, 8, 1, 252, 210, 330, 405, 400, 326, 210, 105, 38, 9, 1 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,4

COMMENTS

Row sums are A116383. Diagonal sums are A116384. First column has e.g.f. Bessel_I(0,2x) (A000984 with interpolated zeros). Second column has e.g.f. Bessel_I(1,2x)+Bessel_I(2,2x) (A037952). Third column has e.g.f. Bessel_I(2,2x)+2*Bessel_I(3,2x)+Bessel_I(4,2x) (A116385). A binomial-Bessel triangle: column k has e.g.f. sum{j=0..k, C(k,j)*Bessel_I(k+j,2x)}.

FORMULA

Riordan array (1/sqrt(1-4x^2), sqrt(1-4x^2)(1-sqrt(1-4x^2))/(x-2x^2+x*sqrt(1-4x^2))); Number triangle T(n,k)=sum{j=0..n, (-1)^(n-j)*C(n,j)*sum{i=0..j, C(j,i-k)C(i,j-i)}}.

EXAMPLE

Triangle begins

1,

0, 1,

2, 1, 1,

0, 3, 2, 1,

6, 4, 5, 3, 1,

0, 10, 10, 8, 4, 1,

20, 15, 21, 19, 12, 5, 1,

0, 35, 42, 42, 32, 17, 6, 1,

70, 56, 84, 92, 77, 50, 23, 7, 1,

0, 126, 168, 192, 180, 131, 74, 30, 8, 1,

252, 210, 330, 405, 400, 326, 210, 105, 38, 9, 1

CROSSREFS

Sequence in context: A087117 A029340 A126258 * A050606 A023416 A080791

Adjacent sequences:  A116379 A116380 A116381 * A116383 A116384 A116385

KEYWORD

easy,nonn,tabl

AUTHOR

Paul Barry (pbarry(AT)wit.ie), Feb 12 2006

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Last modified February 17 10:05 EST 2012. Contains 206009 sequences.