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A124234 Riordan array (1/(1-x), x(1+x)^2). 1
1, 1, 1, 1, 3, 1, 1, 4, 5, 1, 1, 4, 11, 7, 1, 1, 4, 15, 22, 9, 1, 1, 4, 16, 42, 37, 11, 1, 1, 4, 16, 57, 93, 56, 13, 1, 1, 4, 16, 63, 163, 176, 79, 15, 1, 1, 4, 16, 64, 219, 386, 299, 106, 17, 1, 1, 4, 16, 64, 247, 638, 794, 470, 137, 19, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET
0,5
COMMENTS
Row sums are A077864. Diagonal sums are A004695(n+3). T(2n,n) is A032443.
LINKS
FORMULA
T(n,k) = Sum_{j=0..n-k} C(2k,j).
EXAMPLE
Triangle begins
1,
1, 1,
1, 3, 1,
1, 4, 5, 1,
1, 4, 11, 7, 1,
1, 4, 15, 22, 9, 1,
1, 4, 16, 42, 37, 11, 1
PROG
(PARI) tabl(nn) = for (n=0, nn, for (k=0, n, print1(sum(j=0, n-k, binomial(2*k, j)), ", ")); print(); ); \\ Michel Marcus, Nov 05 2016
CROSSREFS
Sequence in context: A334844 A296457 A124020 * A135226 A104730 A249488
KEYWORD
easy,nonn,tabl
AUTHOR
Paul Barry, Oct 22 2006
STATUS
approved

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Last modified March 19 02:58 EDT 2024. Contains 370952 sequences. (Running on oeis4.)