

A110064


a(n+4) = a(n+1)  a(n), a(0) = 1, a(1) = 4, a(2) = 0, a(3) = 1.


3



1, 4, 0, 1, 5, 4, 1, 6, 9, 3, 7, 15, 12, 4, 22, 27, 8, 26, 49, 35, 18, 75, 84, 17, 93, 159, 101, 76, 252, 260, 25, 328, 512, 285, 303, 840, 797, 18, 1143, 1637, 779, 1161, 2780, 2416, 382, 3941, 5196, 2034, 4323, 9137, 7230, 2289, 13460, 16367, 4941, 15749, 29827, 21308, 10808
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OFFSET

0,2


COMMENTS

One of several sequences, apparently all of the form a(n+4) = a(n+1)  a(n), which appear to "spiral outwards" when plotted against each other (see A11006164). In reference to the FAMP program code, A017817 is also in this same batch of sequences and satisfies the same recurrence relation.


LINKS



FORMULA

Expansion of (4*x1)/(1x^3+x^4)


MAPLE

seriestolist(series((1+4*x)/(1x^3+x^4), x=0, 60)); or Floretion Algebra Multiplication Program, FAMP Code: 4kbaseseq[A*B] with A = + .5'i + .5'j + .5'k + .5e and B =  .5'i  .25'j + .25'k  .5i'  .25j' + .25k'  .5'ii'  .25'ij'  .25'ik'  .25'ji'  .25'ki'  .5e


MATHEMATICA

LinearRecurrence[{0, 0, 1, 1}, {1, 4, 0, 1}, 60] (* Harvey P. Dale, Oct 23 2016 *)


CROSSREFS



KEYWORD

easy,sign


AUTHOR



STATUS

approved



