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A045517
Factorials with initial digit '5'.
18
5040, 51090942171709440000, 523022617466601111760007224100074291200000000, 5502622159812088949850305428800254892961651752960000000000
OFFSET
1,1
COMMENTS
Benford's law shows that this sequence will contain about (log 6 - log 5)/log 10 =~ 8% of factorials. [Charles R Greathouse IV, Nov 13 2010]
FORMULA
a(n) = A000142(A045524(n)). - Amiram Eldar, Jul 19 2020
MATHEMATICA
Select[Range[100]!, First[IntegerDigits[#]]==5&] (* Harvey P. Dale, Sep 06 2016 *)
CROSSREFS
For factorials with initial digit d (1 <= d <= 9) see A045509, A045510, A045511, A045516, A045517, A045518, A282021, A045519; A045520, A045521, A045522, A045523, A045524, A045525, A045526, A045527, A045528, A045529. See also A000142.
Sequence in context: A367571 A072242 A271947 * A369181 A068897 A200730
KEYWORD
nonn,base
AUTHOR
STATUS
approved