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A110506 Riordan array (1/(1-xc(2x)),xc(2x)/(1-xc(2x))), c(x) the g.f. of A000108. 5
1, 1, 1, 3, 4, 1, 13, 19, 7, 1, 67, 102, 44, 10, 1, 381, 593, 278, 78, 13, 1, 2307, 3640, 1795, 568, 121, 16, 1, 14589, 23231, 11849, 4051, 999, 173, 19, 1, 95235, 152650, 79750, 28770, 7820, 1598, 234, 22, 1 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,4

COMMENTS

Deleham triangle Delta(0^n,2-0^n) [see construction in A084938]. The binomial transform of the inverse of this triangle has general element (-2)^(n-k)*C(k,n-k), that is, it is the Riordan array (1,x(1-2x)) [A110509]. Row sums are A052701. Diagonal sums are A110508. Inverse is A110511.

FORMULA

Number triangle T(0, k)=0^k, T(n, k)=sum{j=0..n, j*C(2n-j-1, n-j)C(j, k)2^(n-j)}, n, k>0.

T(n,k)=(-1)^(n-k)*A114189(n,k) . - Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Mar 24 2007

EXAMPLE

Rows begin

1;

1,1;

3,4,1;

13,19,7,1;

67,102,44,10,1;

381,593,278,78,13,1;

CROSSREFS

Sequence in context: A109956 A123319 A076785 * A114189 A200659 A059110

Adjacent sequences:  A110503 A110504 A110505 * A110507 A110508 A110509

KEYWORD

easy,nonn,tabl

AUTHOR

Paul Barry (pbarry(AT)wit.ie), Jul 24 2005

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Last modified February 15 23:53 EST 2012. Contains 205860 sequences.