[go: up one dir, main page]

login
A265435
Riordan array (1, x*f(x)) where f(x) is the g.f. of A007564.
1
1, 0, 1, 0, 1, 1, 0, 4, 2, 1, 0, 19, 9, 3, 1, 0, 100, 46, 15, 4, 1, 0, 562, 254, 82, 22, 5, 1, 0, 3304, 1476, 474, 128, 30, 6, 1, 0, 20071, 8893, 2847, 773, 185, 39, 7, 1, 0, 124996, 55046, 17587, 4796, 1165, 254, 49, 8, 1, 0, 793774, 347922, 111006, 30378, 7461, 1665, 336, 60, 9, 1
OFFSET
0,8
COMMENTS
Triangle T(n,k), 0<=k<=n, read by rows, given by (0, 1, 3, 1, 3, 1, 3, 1, 3, ...) DELTA (1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, ...) where DELTA is the operator defined in A084938.
LINKS
EXAMPLE
Triangle begins:
1
0, 1
0, 1, 1
0, 4, 2, 1
0, 19, 9, 3, 1
0, 100, 46, 15, 4, 1
Production matrix begins:
0, 1
0, 1, 1
0, 3, 1, 1
0, 9, 3, 1, 1
0, 27, 9, 3, 1, 1
0, 81, 27, 9, 3, 1, 1
MATHEMATICA
f[x_]:=(1+2*x-Sqrt[1-8*x+4*x^2])/(6*x); T[n_, k_]:=SeriesCoefficient[(x*f[x])^k, {x, 0, n}]; Table[T[n, k], {n, 0, 10}, {k, 0, n}]//Flatten (* Stefano Spezia, Feb 05 2025 *)
CROSSREFS
Cf. A007564, A108524 (row sums).
Sequence in context: A110324 A357586 A266861 * A380841 A277004 A371077
KEYWORD
nonn,tabl,changed
AUTHOR
Philippe Deléham, Dec 09 2015
STATUS
approved