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 A181653 Generalized (conditional) Riordan array with k-th column generated by x^k*(1+x) if k mod 2 = 0, x^k*(1+x+x^2) otherwise. 1
 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 0, 0, 1, 1, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 COMMENTS Row sums are A174296. A181654 is an eigentriangle. LINKS EXAMPLE Triangle begins   1;   1, 1;   0, 1, 1;   0, 1, 1, 1;   0, 0, 0, 1, 1;   0, 0, 0, 1, 1, 1;   0, 0, 0, 0, 0, 1, 1;   0, 0, 0, 0, 0, 1, 1, 1;   0, 0, 0, 0, 0, 0, 0, 1, 1;   0, 0, 0, 0, 0, 0, 0, 1, 1, 1;   0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1; Production matrix begins    1,  1;   -1,  0,  1;    1,  1,  0,  1;    0, -1, -1,  0,  1;    0,  1,  1,  1,  0,  1;    0,  0,  0, -1, -1,  0,  1;    0,  0,  0,  1,  1,  1,  0,  1;    0,  0,  0,  0,  0, -1, -1,  0,  1;    0,  0,  0,  0,  0,  1,  1,  1,  0,  1;    0,  0,  0,  0,  0,  0,  0, -1, -1,  0,  1; CROSSREFS Sequence in context: A163806 A163810 A163804 * A343159 A155091 A145362 Adjacent sequences:  A181650 A181651 A181652 * A181654 A181655 A181656 KEYWORD easy,nonn,tabl AUTHOR Paul Barry, Nov 03 2010 STATUS approved

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Last modified May 11 21:35 EDT 2021. Contains 343808 sequences. (Running on oeis4.)