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 A139595 A139277(n) followed by A139273(n+1). 6
 0, 5, 13, 26, 42, 63, 87, 116, 148, 185, 225, 270, 318, 371, 427, 488, 552, 621, 693, 770, 850, 935, 1023, 1116, 1212, 1313, 1417, 1526, 1638, 1755, 1875, 2000, 2128, 2261, 2397, 2538, 2682, 2831, 2983, 3140, 3300, 3465, 3633, 3806 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Sequence found by reading the line from 0, in the direction 0, 5,... and the same line from 0, in the direction 0, 13,..., in the square spiral whose vertices are the triangular numbers A000217. LINKS Index entries for linear recurrences with constant coefficients, signature (2,0,-2,1) FORMULA Array read by rows: row n gives 8*n^2 + 5n, 8*(n+1)^2 - 3(n+1). G.f. -x*(5+3*x) / ( (1+x)*(x-1)^3 ). - R. J. Mathar, Feb 13 2011 EXAMPLE Array begins: 0, 5 13, 26 42, 63 87, 116 CROSSREFS Cf. A000217, A046092, A139273, A139277, A077221, A139591, A139592, A139593, A139596, A139597, A139598. Sequence in context: A173979 A190446 A188471 * A301673 A301300 A301677 Adjacent sequences:  A139592 A139593 A139594 * A139596 A139597 A139598 KEYWORD easy,nonn AUTHOR Omar E. Pol, May 03 2008 STATUS approved

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Last modified January 27 12:01 EST 2020. Contains 331295 sequences. (Running on oeis4.)