The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A014462 Triangular array formed from elements to left of middle of Pascal's triangle. 7
 1, 1, 1, 3, 1, 4, 1, 5, 10, 1, 6, 15, 1, 7, 21, 35, 1, 8, 28, 56, 1, 9, 36, 84, 126, 1, 10, 45, 120, 210, 1, 11, 55, 165, 330, 462, 1, 12, 66, 220, 495, 792, 1, 13, 78, 286, 715, 1287, 1716, 1, 14, 91, 364, 1001, 2002, 3003, 1, 15, 105, 455, 1365, 3003, 5005, 6435, 1, 16 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS Coefficients for Pontryagin classe of projective spaces. See p. 3 of the Wilson link. Aerated to become a lower triangular matrix with alternating zeros on the diagonal, this matrix appparently becomes the reverse, or mirror, of A117178. - Tom Copeland, May 30 2017 LINKS Reinhard Zumkeller, Rows n = 1..200 of triangle, flattened D. Wilson, Genera: From cobordism to K-theory, Jul 2016. EXAMPLE 1; 1; 1, 3; 1, 4; 1, 5, 10; 1, 6, 15; 1, 7, 21, 35; 1, 8, 28, 56; 1, 9, 36, 84, 126; 1, 10, 45, 120, 210; 1, 11, 55, 165, 330, 462; PROG (Haskell) a014462 n k = a014462_tabf !! (n-1) !! (k-1) a014462_row n = a014462_tabf !! (n-1) a014462_tabf = map reverse a014413_tabf -- Reinhard Zumkeller, Dec 24 2015 CROSSREFS Cf. A014413, A034868, A058622 (row sums). Cf. A001791 (a half-diagonal and diagonal sums). Cf. A007318. Cf. A117178. Sequence in context: A057466 A187079 A086183 * A309992 A016474 A332678 Adjacent sequences:  A014459 A014460 A014461 * A014463 A014464 A014465 KEYWORD tabf,nonn,easy AUTHOR EXTENSIONS More terms from James A. Sellers STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified May 31 06:22 EDT 2020. Contains 334747 sequences. (Running on oeis4.)