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%I #7 Apr 08 2013 11:22:56
%S 0,75,125,5625,40625,390625,7890625,62890625,712890625,3212890625,
%T 68212890625,418212890625,4918212890625,9918212890625,759918212890625,
%U 1259918212890625,6259918212890625,756259918212890625,7256259918212890625,42256259918212890625
%N (5^(2^n) + (10^n)/2) mod 10^n: a sequence of trimorphic numbers ending (for n > 1) in 5.
%C a(n) is the unique nonnegative integer less than 10^n such that a(n) + 2^(n-1) - 1 is divisible by 2^n and a(n) is divisible by 5^n.
%H Eric M. Schmidt, <a href="/A224477/b224477.txt">Table of n, a(n) for n = 1..1000</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/TrimorphicNumber.html">Trimorphic Number</a>
%H <a href="/index/Ar#automorphic">Index entries for sequences related to automorphic numbers</a>
%F a(n) = (A007185(n) + 10^n/2) mod 10^n.
%o (Sage) def A224477(n) : return crt(2^(n-1)+1, 0, 2^n, 5^n)
%Y Cf. A033819. Converges to the 10-adic number A018247. The other trimorphic numbers ending in 5 are included in A007185, A216093, and A224478.
%K nonn,base
%O 1,2
%A _Eric M. Schmidt_, Apr 07 2013
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