OFFSET
0,2
COMMENTS
Set y = x = .5'i + .5'j + .5'k + .5e Define a(0) = 1 (this is twice the coefficient of 'i in x), then "loop" steps 1-5 as described for A108618. a(n) is given by twice the coefficient of 'i (or 'j or 'k) in y from step 4 inside the n-th loop.
Floretion Algebra Multiplication Program, FAMP Code: 2ibasesum(*)seq[ + .5'i + .5'j + .5'k + .5e]
LINKS
N. J. A. Sloane, Table of n, a(n) for n = 0..9999
C. Dement, Plot of A108618 against A108619 (patch on)
C. Dement, Plot of A108618 against A108619 (patch off)
C. Dement, Floretion Online Multiplier
Rémy Sigrist, Colored scatterplot of a(n) for n = 0..9999 (where the color is function of n mod 6)
MATHEMATICA
a[0] = b[0] = 1;
f[n_] := Sign[n]*Mod[n, 2];
a[n_] := a[n] = (1/2)*(a[n-1] - 3*b[n-1]) + 3*f[(1/2)*(a[n-1] + b[n-1])] + f[(1/2)*(a[n-1] - 3*b[n-1])] + 1;
b[n_] := b[n] = (1/2)*(a[n-1] + b[n-1]) + 1;
CROSSREFS
AUTHOR
Creighton Dement, Jun 22 2005
STATUS
approved
