A221221 Where powerbacks and powertrains coincide.

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 22, 24, 33, 42, 44, 55, 66, 77, 88, 99, 101, 111, 112, 113, 114, 115, 116, 117, 118, 119, 121, 131, 141, 151, 161, 171, 181, 191, 202, 211, 212, 213, 214, 215, 216, 217, 218, 219, 222, 232, 242, 252, 262, 272, 282, 292

Offset: 1

Author

Reinhard Zumkeller, May 27 2013

Keywords

• nonn
• base

Comments

Numbers m such that A133048(m) = A133500(m);

A133500(a(n)) = A133048(a(n)) = A222493(n);

if m is a term then also its reversal in decimal representation, palindromes are a subsequence, cf. A004086, A002113.

Examples

			Some non-palindromic terms:
a(11) = 10: A133500(10) = 1^0 = 1 = A133048(10) = A133048(1) = 1;
a(14) = 24: A133500(24) = 2^4 = 16 = A133048(24) = 4^2;
a(16) = 42: A133500(42) = 4^2 = 16 = A133048(42) = 2^4;
a(25) = 112: A133500(112) = 1^1 * 2 = 2 = A133048(112) = 2^1 * 1;
a(26) = 113: A133500(113) = 1^1 * 3 = 3 = A133048(113) = 3^1 * 1;
a(44) = 213: A133500(213) = 2^1 * 3 = 6 = A133048(213) = 3^1 * 2.
		

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Programs

Haskell

a221221 n = a221221_list !! (n-1)
a221221_list = filter (\x -> a133500 x == a133048 x) [0..]