A117488 The number 1 followed by 2*k+1 terms from column k of table A115994.

1, 1, 2, 3, 1, 2, 5, 8, 14, 1, 2, 5, 10, 18, 30, 49, 1, 2, 5, 10, 20, 34, 59, 94, 149, 1, 2, 5, 10, 20, 36, 63, 104, 169, 264, 405, 1, 2, 5, 10, 20, 36, 65, 108, 179, 284, 445, 676, 1017, 1, 2, 5, 10, 20, 36, 65, 110, 183, 294, 465, 716, 1089, 1622, 2387, 1, 2, 5, 10, 20, 36, 65

Offset

1,3

Links

Table of n, a(n) for n=1..71.

Example

Column two of table A115994 begins 1 2 5 8 14 20 30 ... A006918
so row three of A117488 is 1 2 5 8 14.
Triangle starts
1
1 2 3
1 2 5 8 14
1 2 5 10 18 30 49
1 2 5 10 20 34 59 94 149
1 2 5 10 20 36 63 104 169 264 405
1 2 5 10 20 36 65 108 179 284 445 676 1017
1 2 5 10 20 36 65 110 183 294 465 716 1089 1622 2387

Maple

A026820 := proc(n, k) if k > n then combinat[numbpart](n, n) ; else combinat[numbpart](n, k) ; fi ; end: A115994 := proc(n, k) local i ; add(A026820(i, k)*A026820(n-k^2-i, k), i=0..n-k^2) ; end: A117488 := proc(n, k) if k >= 2*n then 0 ; else if n = 1 then 1; else A115994(k+n^2-2*n, n-1) ; fi ; fi ; end: for n from 1 to 10 do for k from 1 to 2*n-1 do printf("%d ", A117488(n, k)) ; od ; od ; # R. J. Mathar, Feb 22 2007

Crossrefs

Cf. A006918, A115994, A117489.

Sequence in context: A109202 A362599 A245559 * A307668 A308173 A256910

Adjacent sequences: A117485 A117486 A117487 * A117489 A117490 A117491

Keyword

tabf,nonn

Author

Alford Arnold, Mar 22 2006

Extensions

More terms from R. J. Mathar, Feb 22 2007

Status

approved