This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A134249 Triangle read by rows, taken from the lower triangular matrix (M * A000012 + A000012 * M) - A000012; where M = lower triangular matrix with (1,1,1,...) in the main diagonal and the triangular numbers in the subdiagonal and A000012 = (1; 1,1; 1,1,1;...). 2
 1, 3, 1, 5, 7, 1, 8, 10, 13, 1, 12, 14, 17, 21, 1, 17, 19, 22, 26, 31, 1, 23, 25, 28, 32, 37, 43, 1, 30, 32, 35, 39, 44, 50, 57, 1, 38, 40, 43, 47, 52, 58, 65, 73, 1, 47, 49, 52, 56, 61, 67, 74, 82, 91, 1 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Row sums = A037235: (1, 4, 13, 32, 65, 116,...). Left column = A134250: (1, 3, 5, 8, 12, 17, 23,...). LINKS EXAMPLE First few rows of the triangle are: 1; 3, 1; 5, 7, 1; 8, 10, 13, 1; 12, 14, 17, 21, 1; 17, 19, 22, 26, 31, 1; 23, 25, 28, 32, 37, 43, 1; ... CROSSREFS Cf. A037235, A134250. Sequence in context: A201552 A216182 A143524 * A188509 A188146 A001607 Adjacent sequences:  A134246 A134247 A134248 * A134250 A134251 A134252 KEYWORD nonn,tabl AUTHOR Gary W. Adamson, Oct 15 2007 EXTENSIONS Edited by N. J. A. Sloane, Nov 01 2009 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .