A088969 Triangle T(n,k), read by rows, given by A000290 DELTA [1, 2, 6, 5, 11, 8, 16, 11, 21, 14, 26, 17, 31, 20, 36, ...] where DELTA is the operator defined in A084938.

1, 0, 1, 0, 1, 3, 0, 5, 20, 21, 0, 61, 287, 445, 231, 0, 1385, 7244, 13688, 11206, 3453, 0, 50521, 285295, 612556, 631862, 320159, 65271, 0, 2702765, 16195816, 38143429, 45667208, 29860381, 10300476, 1491381

Offset

0,6

Links

Table of n, a(n) for n=0..35.

Formula

Row sums : A000657; median Euler numbers (the middle of Arnold's shuttle triangle) Columns : A000007; A000364 (Euler numbers)

Example

Triangle begins:
1;
0, 1;
0, 1, 3;
0, 5, 20, 21;
0, 61, 287, 445, 231;
0, 1385, 7244, 13688, 11206, 3453;
0, 50521, 285295, 612556, 631862, 320159, 65271;
0, 2702765, 16195816, 38143429, 45667208, 29860381, 10300476, 1491381;

Crossrefs

Cf. A000290 A000364 A000657 A084938.

Sequence in context: A328631 A225950 A344503 * A009780 A175677 A129502

Adjacent sequences: A088966 A088967 A088968 * A088970 A088971 A088972

Keyword

easy,nonn,tabl

Author

Philippe Deléham, Oct 29 2003, Nov 07 2007

Status

approved