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A277676 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!. 3
2, 4, 5, 6, 8, 9, 10, 12, 13, 14, 16, 17, 18, 20, 21, 22, 23, 25, 26, 27, 29, 30, 31, 32, 34, 35, 36, 37, 39, 40, 41, 42, 44, 45, 46, 47, 49, 50, 51, 52, 53, 55, 56, 57, 58, 60, 61, 62, 63, 65, 66, 67, 68, 69, 71, 72, 73, 74, 76, 77, 78, 79, 80, 82, 83, 84 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

It has been checked for k = 2..50000 that if d(k+1) > d(k), then d(k+1) = d(k) + 1.

LINKS

Clark Kimberling, Table of n, a(n) for n = 1..1000

FORMULA

(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 *)

PROG

(PARI) d(n) = #digits(n!, n);

isok(n) = d(n+2) > d(n+1); \\ Michel Marcus, Oct 29 2016

CROSSREFS

Cf. A000142, A060151, A277674, A277675.

Sequence in context: A047839 A285601 A139255 * A317551 A004773 A104401

Adjacent sequences:  A277673 A277674 A277675 * A277677 A277678 A277679

KEYWORD

nonn,base,easy

AUTHOR

Clark Kimberling, Oct 26 2016

STATUS

approved

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Last modified July 8 19:20 EDT 2020. Contains 335524 sequences. (Running on oeis4.)