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A277675
Numbers k such that d(k+2) = d(k+1), where d(m) is the number of digits in the base-m representation of m!.
4
1, 3, 7, 11, 15, 19, 24, 28, 33, 38, 43, 48, 54, 59, 64, 70, 75, 81, 87, 93, 98, 104, 110, 116, 122, 128, 135, 141, 147, 153, 159, 166, 172, 179, 185, 192, 198, 205, 211, 218, 224, 231, 238, 244, 251, 258, 265, 271, 278, 285, 292, 299, 306, 313, 320, 327
OFFSET
1,2
COMMENTS
Positions of 0 in A277674.
LINKS
EXAMPLE
(See A277674.)
MATHEMATICA
d = Differences@Array[Floor@Log[#, #!] &, 10000, 2]; (* Robert G. Wilson v, Oct 27 2016 *)
u = Flatten[Position[d, 0]]; (* A277675 *)
v = Flatten[Position[d, 1]]; (* A277676 *)
SequencePosition[Table[IntegerLength[n!, n], {n, 2, 350}], {x_, x_}][[All, 1]] (* Harvey P. Dale, Aug 21 2022 *)
PROG
(PARI) d(n) = #digits(n!, n);
isok(n) = d(n+2) == d(n+1); \\ Michel Marcus, Oct 29 2016
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Clark Kimberling, Oct 26 2016
STATUS
approved