A072549 a(n) = abs(floor(n + a(n-1)/n - n*log(n))).

1, 2, 2, 1, 2, 3, 4, 5, 6, 7, 9, 9, 12, 10, 16, 9, 24, 2, 34, 23, 14, 34, 6, 48, 43, 18, 47, 19, 53, 28, 46, 8, 77, 97, 190, 941, 24503, 16226849, 6929227064868, 1231133018371774314868035

Offset

1,2

Comments

This sequence is based on the cylinder flow equation that is in most fluid dynamics texts. I used a n*log(n) circulation term to slow down the progression that gets very large very fast after n=36.

I take this sequence as an analog of the inverse of the rate of flow in fluid layers around a cylinder and the fluid comes to a near stop when n gets greater than 36. A similar complex plane Julia to this is also possible using the iterative k for the n in this equation and leaving out the absolute value and floor functions.

Links

Table of n, a(n) for n=1..40.

Mathematica

s[0] = 1; s[n_Integer] := s[n] = Abs[Floor[n + s[n - 1]^2/n - n*Log[n]]]; Table[s[n], {n, 0, 40}]

Crossrefs

Sequence in context: A354267 A366804 A259910 * A239481 A200114 A120652

Adjacent sequences: A072546 A072547 A072548 * A072550 A072551 A072552

Keyword

nonn

Author

Roger L. Bagula, Aug 05 2002

Extensions

Edited By Robert G. Wilson v, Aug 08 2002

Status

approved