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A073779
Number of 0's in base-3 representation of n-th prime.
5
0, 1, 0, 0, 1, 0, 0, 1, 0, 2, 1, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 0, 3, 2, 1, 2, 1, 1, 2, 1, 1, 0, 2, 1, 0, 0, 0, 3, 2, 2, 1, 2, 2, 1, 1, 1, 0, 1, 1, 0, 0, 0, 0, 3, 2, 3, 2, 3, 2, 2, 1, 1, 2, 1, 1, 2, 2, 1, 1, 1, 2, 1, 0, 0, 2, 1, 1, 1, 0, 2, 1, 1, 1, 2, 1, 1, 0, 0, 2, 1, 1, 1, 4, 3, 2, 2, 2, 2, 2, 3, 2, 1, 1, 3, 2
OFFSET
1,10
COMMENTS
a(n) = 0 if prime(n) is in A082555. - Robert Israel, Dec 28 2018
LINKS
FORMULA
a(n) = A077267(A000040(n)). - Michel Marcus, Oct 02 2013
EXAMPLE
a(10)=2 as 10th prime is 29 in base-10 representation, or 1002 in base-3 representation.
MAPLE
f:= n -> numboccur(0, convert(ithprime(n), base, 3)):
map(f, [$1..200]); # Robert Israel, Dec 28 2018
MATHEMATICA
A073779[n_] := Length[Cases[IntegerDigits[Prime[n], 3], 0]];
DigitCount[#, 3, 0]&/@Prime[Range[120]] (* Harvey P. Dale, Apr 26 2011 *)
PROG
(Magma) [ Multiplicity({* a: a in Intseq(p, 3) *}, 0): p in PrimesUpTo(600) ]; // Klaus Brockhaus, Oct 10 2010
CROSSREFS
KEYWORD
base,easy,nonn
AUTHOR
Zak Seidov, Aug 11 2002
EXTENSIONS
More terms from Klaus Brockhaus, Oct 10 2010
STATUS
approved