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 A161957 Fixed points of A161955. 0
 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 27, 29, 31, 37, 41, 43, 45, 47, 51, 53, 59, 61, 63, 67, 71, 73, 79, 83, 85, 89, 93, 95, 97, 101, 103, 107, 109, 111, 113, 119, 123, 127, 131, 137, 139, 149, 151, 153, 157, 163, 167, 173, 179, 181, 187, 189, 191, 193, 197, 199 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Fixed points of the TITO2 operation (the TITO operation in binary): numbers a(n) such that A161955(a(n)) = a(n). All numbers in the sequence are odd. All odd primes A065091 belong to the sequence. LINKS Table of n, a(n) for n=1..62. T. Khovanova, Turning Numbers Inside Out [From Tanya Khovanova, Jul 07 2009] EXAMPLE 95 is in this sequence because 95 = 5*19. Prime factors in binary are: 101 and 10011. Reversing them we get 101 and 11001. The product of the last two numbers is 1111101, which is the reverse of the binary representation of 95 (1011111). MATHEMATICA reverseBinPower[{n_, k_}] := FromDigits[Reverse[IntegerDigits[n, 2]], 2]^k fBin[n_] := FromDigits[ Reverse[IntegerDigits[ Times @@ Map[reverseBinPower, FactorInteger[n]], 2]], 2] Select[Range[300], fBin[ # ] == # &] CROSSREFS Cf. A161955, A161594, A161597. Sequence in context: A353076 A033039 A322660 * A082720 A033037 A246413 Adjacent sequences: A161954 A161955 A161956 * A161958 A161959 A161960 KEYWORD base,nonn AUTHOR Tanya Khovanova, Jun 22 2009 EXTENSIONS Comments condensed by R. J. Mathar, Aug 14 2009 STATUS approved

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Last modified September 11 23:02 EDT 2024. Contains 375842 sequences. (Running on oeis4.)