OFFSET
0,3
COMMENTS
Floretion Algebra Multiplication Program, FAMP Code: 1baseiforzapseq[(.5i' + .5j' + .5'ki' + .5'kj')*(.5'i + .5'j + .5'ik' + .5'jk')], 1vesforzap = A000004
LINKS
Colin Barker, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (0,1,2,-1,0,1,2).
FORMULA
a(n) = a(n-2) + 2*a(n-3) - a(n-4) + a(n-6) + 2*a(n-7) for n>6. - Colin Barker, Apr 30 2019
MATHEMATICA
CoefficientList[Series[-x(x^2+1)(x+1)^2/((2x^3+x^2-1)(x^4+1)), {x, 0, 50}], x] (* or *) LinearRecurrence[ {0, 1, 2, -1, 0, 1, 2}, {0, 1, 2, 3, 6, 7, 10}, 50] (* Harvey P. Dale, May 03 2024 *)
PROG
(PARI) a(n)=([0, 1, 0, 0, 0, 0, 0; 0, 0, 1, 0, 0, 0, 0; 0, 0, 0, 1, 0, 0, 0; 0, 0, 0, 0, 1, 0, 0; 0, 0, 0, 0, 0, 1, 0; 0, 0, 0, 0, 0, 0, 1; 2, 1, 0, -1, 2, 1, 0]^n*[0; 1; 2; 3; 6; 7; 10])[1, 1] \\ Charles R Greathouse IV, Oct 03 2016
(PARI) concat(0, Vec(x*(1 + x)^2*(1 + x^2) / ((1 - x^2 - 2*x^3)*(1 + x^4)) + O(x^45))) \\ Colin Barker, Apr 30 2019
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Creighton Dement, May 25 2005
STATUS
approved