A085852 Triangle T(n, k) read by rows; given by [0, 1, 0, 2, 0, 3, 0, 4, ...] DELTA [1, 0, 2, 0, 2, 0, 3, 0, 2, 0, 4, 0, 2, 0, ...] (A000005 interspersed with 0's) where DELTA is Deléham's operator defined in A084938.

1, 0, 1, 0, 1, 1, 0, 1, 4, 1, 0, 1, 11, 11, 1, 0, 1, 26, 62, 26, 1, 0, 1, 57, 266, 258, 57, 1, 0, 1, 120, 991, 1792, 903, 120, 1, 0, 1, 247, 3405, 10363, 9483, 2829, 247, 1, 0, 1, 502, 11140, 53818, 80342, 42906, 8212, 502, 1, 0, 1, 1013, 35348, 260996

Offset: 0

Author

N. J. A. Sloane, Aug 16 2003

Keywords

• nonn
• tabl

Examples

			Triangle begins:
1,
0, 1,
0, 1, 1,
0, 1, 4, 1,
0, 1, 11, 11, 1,
0, 1, 26, 62, 26, 1,
0, 1, 57, 266, 258, 57, 1,
0, 1, 120, 991, 1792, 903, 120, 1,
0, 1, 247, 3405, 10363, 9483, 2829, 247, 1,
0, 1, 502, 11140, 53818, 80342, 42906, 8212, 502, 1,
...
		

Links

• Alois P. Heinz, Rows n = 0..140, flattened

Crossrefs

Cf. A000295 (3rd column), A000460 (4th column), A000498 (5th column).

Programs

Mathematica

m = 13;
(* DELTA is defined in A084938 *)
DELTA[LinearRecurrence[{0, 2, 0, -1}, {0, 1, 0, 2}, m], Table[ {DivisorSigma[0, n], 0}, {n, 1, m}] // Flatten, m] // Flatten (* Jean-François Alcover, Feb 19 2020 *)

Extensions

Incorrect comment removed by Philippe Deléham, Sep 25 2015