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A221221
Where powerbacks and powertrains coincide.
5
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
1,3
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.
LINKS
EXAMPLE
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.
PROG
(Haskell)
a221221 n = a221221_list !! (n-1)
a221221_list = filter (\x -> a133500 x == a133048 x) [0..]
CROSSREFS
Sequence in context: A362076 A276512 A023792 * A355224 A178354 A179309
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, May 27 2013
STATUS
approved