Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #13 Oct 20 2024 04:08:39
%S 0,0,0,1,1,1,1,0,1,0,1,1,0,0,0,1,0,0,0,0,1,2,1,1,2,2,1,1,2,0,0,1,2,2,
%T 2,3,2,2,2,0,0,1,2,3,3,2,2,2,3,0,1,2,2,3,4,2,3,3,3,0,1,2,3,2,2,4,4,4,
%U 4,0,0,1,2,2,1,4,4,4,4,0,0,1
%N Number of bases in which both n and the reversal of n are 3-digit numbers.
%F a(n) = a(inv(n)).
%F a(A002113(n)) = A191291(A002113(n)).
%F a(n) <= min(A191291(n),A191291(inv(n))).
%e a(36)=3 since 36 is 3-digit number in bases 4,5,6 and 63 is 3-digit number in bases 4,5,6,7 such that we have 3 common bases.
%Y Cf. A002113, A191291.
%K nonn,base
%O 1,22
%A _Vladimir Shevelev_, May 30 2011