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A166335 Exponential Riordan array [1+x*sinh(x), x]. 2
1, 0, 1, 2, 0, 1, 0, 6, 0, 1, 4, 0, 12, 0, 1, 0, 20, 0, 20, 0, 1, 6, 0, 60, 0, 30, 0, 1, 0, 42, 0, 140, 0, 42, 0, 1, 8, 0, 168, 0, 280, 0, 56, 0, 1, 0, 72, 0, 504, 0, 504, 0, 72, 0, 1, 10, 0, 360, 0, 1260, 0, 840, 0, 90, 0, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,4

LINKS

Table of n, a(n) for n=0..65.

FORMULA

Number triangle T(n,k)=[k<=n]*C(n,k)*((n-k)+0^((n-k)/2))(1+(-1)^(n-k))/2.

EXAMPLE

Triangle begins

1,

0, 1,

2, 0, 1,

0, 6, 0, 1,

4, 0, 12, 0, 1,

0, 20, 0, 20, 0, 1,

6, 0, 60, 0, 30, 0, 1,

0, 42, 0, 140, 0, 42, 0, 1,

8, 0, 168, 0, 280, 0, 56, 0, 1,

0, 72, 0, 504, 0, 504, 0, 72, 0, 1,

10, 0, 360, 0, 1260, 0, 840, 0, 90, 0, 1

MATHEMATICA

(* The function RiordanArray is defined in A256893. *)

RiordanArray[1 + # Sinh[#]&, #&, 11, True] // Flatten (* Jean-Fran├žois Alcover, Jul 19 2019 *)

CROSSREFS

Row sums are A131056. Diagonal sums are A166336. Central coefficients are A166337.

Sequence in context: A229141 A137526 A137525 * A109187 A265089 A166357

Adjacent sequences:  A166332 A166333 A166334 * A166336 A166337 A166338

KEYWORD

easy,nonn,tabl

AUTHOR

Paul Barry, Oct 12 2009

STATUS

approved

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Last modified October 3 18:24 EDT 2022. Contains 357237 sequences. (Running on oeis4.)