A085852 - OEIS

%I #21 Feb 19 2020 12:05:57

%S 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,

%T 1,120,991,1792,903,120,1,0,1,247,3405,10363,9483,2829,247,1,0,1,502,

%U 11140,53818,80342,42906,8212,502,1,0,1,1013,35348,260996

%N 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.

%H Alois P. Heinz, <a href="/A085852/b085852.txt">Rows n = 0..140, flattened</a>

%e Triangle begins:

%e 1,

%e 0, 1,

%e 0, 1, 1,

%e 0, 1, 4, 1,

%e 0, 1, 11, 11, 1,

%e 0, 1, 26, 62, 26, 1,

%e 0, 1, 57, 266, 258, 57, 1,

%e 0, 1, 120, 991, 1792, 903, 120, 1,

%e 0, 1, 247, 3405, 10363, 9483, 2829, 247, 1,

%e 0, 1, 502, 11140, 53818, 80342, 42906, 8212, 502, 1,

%e ...

%t m = 13;

%t (* DELTA is defined in A084938 *)

%t 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 *)

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

%K nonn,tabl

%O 0,9

%A _N. J. A. Sloane_, Aug 16 2003

%E Incorrect comment removed by _Philippe Deléham_, Sep 25 2015