

A162742


Reverse digits in the binary representation of each prime base in the prime factorization of n.


2



1, 1, 3, 1, 5, 3, 7, 1, 9, 5, 13, 3, 11, 7, 15, 1, 17, 9, 25, 5, 21, 13, 29, 3, 25, 11, 27, 7, 23, 15, 31, 1, 39, 17, 35, 9, 41, 25, 33, 5, 37, 21, 53, 13, 45, 29, 61, 3, 49, 25, 51, 11, 43, 27, 65, 7, 75, 23, 55, 15, 47, 31, 63, 1, 55, 39, 97, 17, 87, 35, 113, 9, 73, 41, 75, 25, 91, 33
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,3


COMMENTS

Base2 variant of A071786: apply the bitreversion A030101 to each of the primes in the bases of the prime factorization of n.


LINKS

Alois P. Heinz, Table of n, a(n) for n = 1..20000


FORMULA

A161955(n) = A030101(a(n)).


EXAMPLE

At n=8=2^3, represent 2 as 10 in binary, reverse 10 to give 1, and recombine as 1^3=1 = a(8). At n=14=2*7 =(10)*(111) in binary, reverse the factors to give (1)*(111)=1*7=7=a(14).


MAPLE

A030101 := proc(n) local dgs ; dgs := convert(n, base, 2) ; add( op(i, dgs)*2^(i1), i=1..nops(dgs)) ; end:
A162742 := proc(n) local a, p ; a := 1 ; for p in ifactors(n)[2] do a := a* A030101(op(1, p))^op(2, p) ; od: a; end:


CROSSREFS

Sequence in context: A171968 A093474 A030101 * A081432 A318060 A136655
Adjacent sequences: A162739 A162740 A162741 * A162743 A162744 A162745


KEYWORD

base,easy,nonn,mult


AUTHOR

R. J. Mathar, Jul 12 2009


EXTENSIONS

Cleaned up the definition and corrected the second example  R. J. Mathar, Aug 03 2009


STATUS

approved



