A129685 Exponential Riordan array [1-x^2/2, x].

1, 0, 1, -1, 0, 1, 0, -3, 0, 1, 0, 0, -6, 0, 1, 0, 0, 0, -10, 0, 1, 0, 0, 0, 0, -15, 0, 1, 0, 0, 0, 0, 0, -21, 0, 1, 0, 0, 0, 0, 0, 0, -28, 0, 1, 0, 0, 0, 0, 0, 0, 0, -36, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, -45, 0, 1

Offset

0,8

Links

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

Example

Triangle begins
1,
0, 1,
-1, 0, 1,
0, -3, 0, 1,
0, 0, -6, 0, 1,
0, 0, 0, -10, 0, 1,
0, 0, 0, 0, -15, 0, 1,
0, 0, 0, 0, 0, -21, 0, 1,
0, 0, 0, 0, 0, 0, -28, 0, 1,
0, 0, 0, 0, 0, 0, 0, -36, 0, 1,
0, 0, 0, 0, 0, 0, 0, 0, -45, 0, 1

Mathematica

(* The function RiordanArray is defined in A256893. *)
RiordanArray[1 - #^2/2&, #&, 11, True] // Flatten (* Jean-François Alcover, Jul 19 2019 *)

Crossrefs

Inverse of A129684. Row sums are A080956.

Sequence in context: A106216 A035676 A369283 * A292835 A372503 A318499

Adjacent sequences: A129682 A129683 A129684 * A129686 A129687 A129688

Keyword

easy,sign,tabl

Author

Paul Barry, Apr 28 2007

Status

approved