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 A131843 Triangle read by rows: 2*A131821 - A000012. 4
 1, 3, 3, 5, 1, 5, 7, 1, 1, 7, 9, 1, 1, 1, 9, 11, 1, 1, 1, 1, 11, 13, 1, 1, 1, 1, 1, 13, 15, 1, 1, 1, 1, 1, 1, 15, 17, 1, 1, 1, 1, 1, 1, 1, 17, 19, 1, 1, 1, 1, 1, 1, 1, 1, 19, 21, 1, 1, 1, 1, 1, 1, 1, 1, 1, 21, 23, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 23, 25, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 25, 27, 1, 1, 1, 1, 1 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Row sums = 5*n + 1, A016861: (1, 6, 11, 16, 21, ...). LINKS B. D. Swan, Table of n, a(n) for n = 0..100000 FORMULA 2*A131821 - A000012 as an infinite lower triangular matrix. 2*n - 1, (1, 3, 5, 7, ...) as right and left borders, with the rest zeros. EXAMPLE First few rows of the triangle are:    1;    3,  3;    5,  1,  5;    7,  1,  1,  7;    9,  1,  1,  1,  9;   11,  1,  1,  1,  1, 11;   ... CROSSREFS Cf. A016861, A131821. Sequence in context: A205853 A240594 A079887 * A205550 A209389 A105104 Adjacent sequences:  A131840 A131841 A131842 * A131844 A131845 A131846 KEYWORD nonn,tabl,easy AUTHOR Gary W. Adamson, Jul 21 2007 EXTENSIONS Corrected and edited by B. D. Swan (bdswan(AT)gmail.com), Dec 20 2008 STATUS approved

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