

A130074


Nonprimes n such that n divides 5^n  3^n  2^n = A130072(n).


4



1, 4, 6, 8, 9, 12, 15, 16, 18, 24, 25, 27, 32, 36, 44, 45, 48, 54, 64, 72, 75, 81, 95, 96, 108, 125, 128, 133, 135, 144, 162, 175, 192, 216, 225, 243, 256, 264, 288, 324, 325, 361, 375, 384, 405, 432, 475, 486, 512, 561, 576, 594, 618, 625, 648, 675, 704, 729, 768
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OFFSET

1,2


COMMENTS

Numbers n such that n divides A130072(n) are listed in A130073(n) = {1,2,3,4,5,6,7,8,9,11,12,13,15,16,17,18,19,23,24,25,27,29,31,32,36,37,41,43,...}, which includes all primes. a(n) includes nonprimes in A130073(n). p^(k+1) divides A130072(p^k) for prime p = {2,3,5,19} = A130076(n) and all k>0. It appears that a(n) includes all powers p^k of primes p = {2,3,5,19} for k>1 and all powers of numbers of the form 2^k*3^m, 3^k*5^m, 5^k*19^m.


LINKS

Table of n, a(n) for n=1..59.


MATHEMATICA

Select[Range[10000], !PrimeQ[ # ]&&IntegerQ[(PowerMod[5, #, # ]PowerMod[3, #, # ]PowerMod[2, #, # ])/# ]&]


CROSSREFS

Cf. A130072, A130073, A130075, A130076.
Sequence in context: A100425 A258614 A269131 * A304242 A067012 A157942
Adjacent sequences: A130071 A130072 A130073 * A130075 A130076 A130077


KEYWORD

nonn


AUTHOR

Alexander Adamchuk, May 06 2007


STATUS

approved



