A191322 Number of bases in which both n and the reversal of n are 3-digit numbers.

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, 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, 4, 0, 0, 1, 2, 2, 1, 4, 4, 4, 4, 0, 0, 1

Offset: 1

Author

Vladimir Shevelev, May 30 2011

Keywords

• nonn
• base

Examples

			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.
		

Crossrefs

Cf. A002113, A191291.

Formula

a(n) = a(inv(n)).

a(A002113(n)) = A191291(A002113(n)).

a(n) <= min(A191291(n),A191291(inv(n))).