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A171774 Radix expansion of -1/6 in radix -exp(Pi/sqrt(3)). 1
1, 0, 1, 1, 0, 0, 2, 0, 1, 0, 0, 1, 2, 0, 0, 1, 0, 0, 2, 0, 2, 0, 0, 0, 1, 0, 1, 2, 0, 0, 2, 0, 0, 0, 0, 1, 2, 0, 2, 0, 0, 0, 2, 0, 0, 0, 0, 1, 3, 0, 0, 2, 0, 0, 0, 0, 2, 0, 0, 0, 2, 0, 2, 1, 0, 0, 2, 0, 0, 0, 0, 0, 2, 0, 1, 2, 0, 0, 2, 0, 1, 0, 0, 2, 0, 0, 0, 0, 0, 0, 4, 0, 2, 0, 0, 0, 2, 0, 0, 1, 0, 0, 2, 0, 0 (list; graph; refs; listen; history; text; internal format)
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

Differs from A002324 for the first time at n = 300, where a(300) = 0, while A002324(300) = 1.

Sequence in context: A145171 A117154 A074941 * A002324 A101671 A078979

Adjacent sequences:  A171771 A171772 A171773 * A171775 A171776 A171777

KEYWORD

nonn

AUTHOR

Michael Somos, Dec 18 2009

STATUS

approved

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Last modified January 21 11:01 EST 2020. Contains 331105 sequences. (Running on oeis4.)