%I #5 Feb 27 2015 16:45:02
%S 1,4,7,3,3,6,3,3,3,6,3,3,3,3,6,3,3,3,3,3,6,3,3,3,3,3,3,6,3,3,3,3,3,3,
%T 3,6,3,3,3,3,3,3,3,3,6,3,3,3,3,3,3,3,3,3,6,3,3,3,3,3,3,3,3,3,3,6,3,3,
%U 3,3,3,3,3,3,3,3,3,6,3,3,3,3,3,3,3,3
%N Initial digits of A237424 in decimal representation.
%C a(n) = A000030(A237424(n));
%C n with a(n) = 3: A237424(n) = (10^a+10^b+1)/3 with 0 <= b < a, see also A014132;
%C n with a(n) = 6: A237424(n) = (10^a+10^b+1)/3 with a = b, see also A199682, A254338;
%C length of k-th run of consecutive 3s = k+1, k > 0;
%C digits 0, 2, 5, 8 and 9 do not occur.
%H Reinhard Zumkeller, <a href="/A254397/b254397.txt">Table of n, a(n) for n = 1..10000</a>
%o (Haskell)
%o a254397 = a000030 . a237424
%Y Cf. A237424, A000030, A254339.
%K nonn,base
%O 1,2
%A _Reinhard Zumkeller_, Feb 23 2015