A071301 Denominator of b(n), where b(n+1) = Sum_{k=0..n} b'((n^2-k^2)/n), b(0) = b(1) = 1, and b'(x) = b(x) if x is an integer and is linearly interpolated otherwise.

1, 1, 1, 2, 6, 3, 15, 60, 70, 140, 540, 37800, 8316, 207900, 1351350, 75675600, 141891750, 11176704, 308756448000, 222304642560, 15084957888000, 234654900480000, 1267136462592000, 139385010885120000, 213723683357184000

Offset

0,4

Links

Table of n, a(n) for n=0..24.

Example

b(4) = b'(9/3)+b'(8/3)+b'(5/3)+b'(0/3) = b(3)+[(1/3)b(2)+(2/3)b(3)]+[(1/3)b(1)+(2/3)b(2)]+b(0) = 65/6.

Crossrefs

Cf. A071298, A071299, A071300.

Sequence in context: A056839 A302033 A337643 * A145642 A056195 A083169

Adjacent sequences: A071298 A071299 A071300 * A071302 A071303 A071304

Keyword

nonn,easy,frac

Author

Michele Dondi (blazar(AT)lcm.mi.infn.it), Jun 10 2002

Extensions

More terms from David Wasserman, Nov 08 2005

Edited by N. J. A. Sloane, May 20 2019

Status

approved