A107307 Expansion of g.f. (1-x-2*x^2-x^3+x^4)/((x-1)^3*(6*x^2+2*x-1)).

1, 4, 15, 51, 183, 655, 2381, 8653, 31539, 114927, 419001, 1527457, 5568791, 20302171, 74016909, 269846637, 983794491, 3586668535, 13076103713, 47672218297, 173801058495, 633635426355, 2310077203221, 8421966964069

Offset

0,2

Comments

The definition of this sequence given in the program code is, without a doubt, involved. This is in contrast to its "relatively simple" generating function (which came as a small surprise). At least in principle, it is certainly possible that a simpler definition involving floretions can be found.

Floretion Algebra Multiplication Program, FAMP Code: Fortype: Type 1A Roktype: (left factor): Y[sqa.Findk()] = Y[sqa.Findk()] - Math.signum(Y[sqa.Findk()])*p (internal program code) Roktype (right factor): Do nothing. Fiztype: ChuRed (a(n)) = jessigforcycfizholrok(infty)-1jessigforcycfizholrokseq[(.5'j + .5j' + e)(- .5'i + .5'j - .5i' + .5j' - 'kk' - .5'ik' - .5'jk' - .5'ki' - .5'kj')]

Links

Table of n, a(n) for n=0..23.

Index entries for linear recurrences with constant coefficients, signature (5,-3,-11,16,-6).

Crossrefs

Sequence in context: A196835 A055218 A303843 * A240365 A005492 A003013

Adjacent sequences: A107304 A107305 A107306 * A107308 A107309 A107310

Keyword

nonn,easy

Author

Creighton Dement, May 20 2005

Status

approved