A079099 Number of 0's in n primorial or 0's in A002110(n).

0, 0, 1, 1, 1, 3, 2, 1, 2, 1, 5, 2, 3, 4, 1, 3, 4, 3, 5, 4, 5, 4, 3, 5, 4, 8, 2, 3, 3, 6, 6, 7, 12, 12, 6, 6, 5, 9, 7, 8, 7, 7, 10, 9, 5, 9, 7, 9, 10, 17, 12, 11, 16, 16, 13, 10, 10, 14, 11, 14, 9, 16, 11, 14, 8, 13, 16, 14, 4, 15, 15, 17, 9, 19, 15, 17, 17, 22, 15, 12, 19, 14, 18, 11, 21, 19

Offset

2,6

Comments

The sum of the reciprocals appear to converge.

Links

Table of n, a(n) for n=2..87.

Mathematica

DigitCount[#, 10, 0]&/@FoldList[Times, Prime[Range[90]]] (* Harvey P. Dale, Mar 05 2022 *)

Prog

(PARI) \ prime factorials p# = p1*p2*p3... where pi is the ithprime prfactdg(n, dg) = { forprime(j=2, n, y=1; ct=sr=0; forprime(x=2, j, y*=x; ); y1 = Str(y); print1(y" "); ln = length(y1); for(k = 1, ln, d = y%10; y = floor(y/10); if(d ==dg, ct+=1; sr += 1.0/ct; ); ); print1(ct", "); ); print(); print(sr); }

Crossrefs

Sequence in context: A254629 A096248 A079109 * A213195 A256794 A366899

Adjacent sequences: A079096 A079097 A079098 * A079100 A079101 A079102

Keyword

easy,nonn

Author

Cino Hilliard, Feb 03 2003

Status

approved