This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A085852 #21 Feb 19 2020 12:05:57 %S A085852 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 A085852 1,120,991,1792,903,120,1,0,1,247,3405,10363,9483,2829,247,1,0,1,502, %U A085852 11140,53818,80342,42906,8212,502,1,0,1,1013,35348,260996 %N 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. %H A085852 Alois P. Heinz, <a href="/A085852/b085852.txt">Rows n = 0..140, flattened</a> %e A085852 Triangle begins: %e A085852 1, %e A085852 0, 1, %e A085852 0, 1, 1, %e A085852 0, 1, 4, 1, %e A085852 0, 1, 11, 11, 1, %e A085852 0, 1, 26, 62, 26, 1, %e A085852 0, 1, 57, 266, 258, 57, 1, %e A085852 0, 1, 120, 991, 1792, 903, 120, 1, %e A085852 0, 1, 247, 3405, 10363, 9483, 2829, 247, 1, %e A085852 0, 1, 502, 11140, 53818, 80342, 42906, 8212, 502, 1, %e A085852 ... %t A085852 m = 13; %t A085852 (* DELTA is defined in A084938 *) %t A085852 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 A085852 Cf. A000295 (3rd column), A000460 (4th column), A000498 (5th column). %K A085852 nonn,tabl %O A085852 0,9 %A A085852 _N. J. A. Sloane_, Aug 16 2003 %E A085852 Incorrect comment removed by _Philippe Deléham_, Sep 25 2015