OFFSET
1,7
LINKS
Michael Somos, Table of n, a(n) for n = 1..10000
FORMULA
If r = -exp(Pi/sqrt(3)) and q = 1/r, then -1/6 = Sum_{k>0} a(k) * q^k.
EXAMPLE
q + q^3 + q^4 + 2*q^7 + q^9 + q^12 + 2*q^13 + q^16 + 2*q^19 + 2*q^21 + ...
PROG
(PARI) {a(n) = local(x, r, k); if( n<1, 0, default(realprecision, n ); r = -exp(Pi / sqrt(3)); x = -r/6; for(i=1, n, x = (x - (k = if(x>0, round(x), 0)))*r); k)};
CROSSREFS
KEYWORD
nonn
AUTHOR
Michael Somos, Dec 18 2009
STATUS
approved