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A071638 Numbers n such that phi(n) = b(n,1)^b(n,0) where b(n,1) is the number of 1's in binary representation of n and b(n,0) the number of 0's. 0
1, 2, 6, 10, 12, 20, 24, 34, 40, 48, 60, 68, 80, 85, 96, 136, 160, 192, 272, 320, 384, 399, 514, 544, 640, 768, 1028, 1088, 1280, 1536, 2040, 2056, 2176, 2560, 3072, 4112, 4352, 5120, 6144, 8224, 8704, 10240, 12288, 13805, 16448, 17408, 20480, 24576 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..48.

PROG

(PARI) for(s=1, 100000, if(sum(i=1, length(binary(s)), if(component(binary(s), i)-1, 0, 1))^sum(i=1, length(binary(s)), if(component(binary(s), i), 0, 1))==eulerphi(s), print1(s, ", ")))

CROSSREFS

Cf. A023416, A000120.

Sequence in context: A263309 A253913 A190789 * A028348 A214963 A140776

Adjacent sequences:  A071635 A071636 A071637 * A071639 A071640 A071641

KEYWORD

easy,nonn

AUTHOR

Benoit Cloitre, Jun 22 2002

STATUS

approved

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Last modified January 27 22:48 EST 2022. Contains 350654 sequences. (Running on oeis4.)