This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A074755 #15 May 13 2025 00:54:34
%S A074755 5,7,13,11,11,13,12,13,12,13,13,11,10,12,12,13,12,12,12,11,13,12,12,
%T A074755 10,10,13,13,13,11,13,12,10,10,11,11,13,13,10,13,11,13,12,13,12,12,13,
%U A074755 12,12,12,12,12,11,10,10,13,13,13,13,13,13,11,13,12,10,11,11,13
%N A074755 Number of n-digit non-leading-zero trimorphic numbers (m such that m^3 ends in m).
%C A074755 For n >= 3, I can show 8 <= a(n) <= 13 and I highly suspect that 10 <= a(n) <= 13 from empirical evidence.
%C A074755 If n >= 3, there are 15 integers 0 <= x < 10^n with x == 0, 1 or -1 mod 5^n and x == 0, 1, -1, 2^(n-1)-1 or 2^(n-1)+1 mod 2^n, and a(n) is the number of these that are >= 10^(n-1). - _Robert Israel_, Jul 07 2014
%H A074755 Eric M. Schmidt, <a href="/A074755/b074755.txt">Table of n, a(n) for n = 1..1000</a>
%p A074755 f:= n ->
%p A074755 nops(select(`>=`,{seq(seq(chrem([a,b],[2^n,5^n]),a={0,1,2^(n-1)-1,2^(n-1)+1,-1}),b={0,1,-1})},10^(n-1))):
%p A074755 seq(f(n), n=1..100); # _Robert Israel_, Jul 07 2014
%Y A074755 Cf. A033819.
%K A074755 nonn,base
%O A074755 1,1
%A A074755 _David W. Wilson_, Sep 28 2002