A073779 Number of 0's in base-3 representation of n-th prime.

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

Robert Israel, Table of n, a(n) for n = 1..10000

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

Cf. A073780, A073781, A077267, A082555.

Sequence in context: A319368 A092410 A100204 * A081227 A301469 A004610

Adjacent sequences: A073776 A073777 A073778 * A073780 A073781 A073782

Keyword

base,easy,nonn

Author

Zak Seidov, Aug 11 2002

Extensions

More terms from Klaus Brockhaus, Oct 10 2010

Status

approved