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A048867 Numbers for which reduced residue system contains fewer primes than nonprimes. 1
1, 2, 11, 13, 17, 19, 23, 25, 27, 29, 31, 33, 35, 37, 39, 41, 43, 47, 49, 51, 53, 55, 57, 59, 61, 63, 65, 67, 69, 71, 73, 75, 77, 79, 81, 83, 85, 87, 89, 91, 93, 94, 95, 97, 99, 101, 103, 106, 107, 109, 111, 113, 115, 117, 118, 119, 121, 122, 123, 124, 125, 127, 128 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

EXAMPLE

Large primes belong to this set. Composites like: n=35 has 2 prime divisors, Phi(35)=24 Pi(35)=11; In reduced residue system 9 primes and 15 nonprimes occur.

CROSSREFS

A000720(n)-A001221(n) < A000010(n) -[ A000720(n)-A001221(n) ]

Sequence in context: A127303 A068972 A116437 * A113626 A154539 A137238

Adjacent sequences:  A048864 A048865 A048866 * A048868 A048869 A048870

KEYWORD

nonn

AUTHOR

Labos E. (labos(AT)ana.sote.hu)

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Last modified February 15 13:09 EST 2012. Contains 205789 sequences.