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A079099
Number of 0's in n primorial or 0's in A002110(n).
0
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.
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
KEYWORD
easy,nonn
AUTHOR
Cino Hilliard, Feb 03 2003
STATUS
approved