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A332242
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Numbers k such that k! has exactly k nonzero decimal digits.
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0
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OFFSET
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1,2
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COMMENTS
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No other terms < 100000.
Conjecture: these 6 terms are the only terms of the sequence, i.e., there are no terms larger than 57.
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LINKS
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FORMULA
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EXAMPLE
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48! = 12413915592536072670862289047373375038521486354677760000000000 has 48 nonzero decimal digits, so 48 is a term.
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MAPLE
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q:= n-> nops(subs(0=NULL, convert(n!, base, 10)))=n:
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PROG
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(Python)
while i < 1000:
s = str(n)
if len(s) - s.count('0') == i:
i += 1
n *= i
(PARI) isok(k) = #select(x->(x != 0), digits(k!)) == k; \\ Michel Marcus, Feb 08 2020
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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