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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!.

%I A277675 #17 Aug 21 2022 19:37:36
%S A277675 1,3,7,11,15,19,24,28,33,38,43,48,54,59,64,70,75,81,87,93,98,104,110,
%T A277675 116,122,128,135,141,147,153,159,166,172,179,185,192,198,205,211,218,
%U A277675 224,231,238,244,251,258,265,271,278,285,292,299,306,313,320,327
%N 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!.
%C A277675 Positions of 0 in A277674.
%H A277675 Clark Kimberling, <a href="/A277675/b277675.txt">Table of n, a(n) for n = 1..1000</a>
%e A277675 (See A277674.)
%t A277675 d = Differences@Array[Floor@Log[#, #!] &, 10000, 2]; (* _Robert G. Wilson v_, Oct 27 2016 *)
%t A277675 u = Flatten[Position[d, 0]]; (* A277675 *)
%t A277675 v = Flatten[Position[d, 1]]; (* A277676 *)
%t A277675 SequencePosition[Table[IntegerLength[n!,n],{n,2,350}],{x_,x_}][[All,1]] (* _Harvey P. Dale_, Aug 21 2022 *)
%o A277675 (PARI) d(n) = #digits(n!, n);
%o A277675 isok(n) = d(n+2) == d(n+1); \\ _Michel Marcus_, Oct 29 2016
%Y A277675 Cf. A000142, A060151, A277674, A277676.
%K A277675 nonn,base,easy
%O A277675 1,2
%A A277675 _Clark Kimberling_, Oct 26 2016