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A171243
Riordan array (f(x), x*g(x)), f(x) is the g.f. of A126952, g(x) is the g.f. of A117641.
2
1, 1, 1, 5, 1, 1, 21, 6, 1, 1, 93, 25, 7, 1, 1, 421, 112, 29, 8, 1, 1, 1937, 510, 132, 33, 9, 1, 1, 9017, 2357, 606, 153, 37, 10, 1, 1, 42349, 11009, 2819, 709, 175, 41, 11, 1, 1, 200277, 51840, 13233, 3324, 819, 198, 45, 12, 1, 1
OFFSET
0,4
COMMENTS
Expansion of row sums of T_(x,3), T_(x,y) defined in A039599.
Matrix product P^3 * Q * P^(-3), where P denotes Pascal's triangle A007318 and Q denotes A061554 (formed from P by sorting the rows into descending order). Cf. A158793 and A158815. - Peter Bala, Jul 13 2021
FORMULA
Sum_{k=0..n} T(n,k)*x^k = A126952(n), A126568(n), A026375(n), A026378(n+1), A000351(n) for x = 0,1,2,3,4 respectively.
EXAMPLE
Triangle begins:
1;
1, 1;
5, 1, 1;
21, 6, 1, 1;
93, 25, 7, 1, 1;
421, 112, 29, 8, 1, 1;
...
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Philippe Deléham, Dec 06 2009
STATUS
approved