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A175486 Composite numbers of form 8n+5 with all prime factors of form 8m+5. 0
125, 325, 725, 845, 925, 1325, 1525, 1885, 2197, 2405, 2525, 2725, 3125, 3445, 3725, 3925, 3965, 4205, 4325, 4525, 4901, 4925, 5365, 5725, 6253, 6565, 6725, 6845, 6925, 7085, 7325, 7685, 7925, 8125, 8725, 8845, 8957, 9325, 9685, 9725, 9805, 9925, 10205 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

There are no squares and no semiprimes in the sequence.

LINKS

Table of n, a(n) for n=1..43.

EXAMPLE

125=5^3, 325=5^2*13, 725=5^2*29.

MATHEMATICA

Do[nn=8n+5; If[ !PrimeQ[nn]&&{5}==Union[Mod[(fi=First/@FactorInteger[nn]), 8]], Print[nn]], {n, 2*10^3}]

CROSSREFS

Cf. A004770 Numbers of form 8n+5, A175461 Semiprimes of form 8n+5, A007521 Primes of form 8n+5.

Sequence in context: A253226 A223182 A256362 * A250579 A161855 A353502

Adjacent sequences:  A175483 A175484 A175485 * A175487 A175488 A175489

KEYWORD

nonn

AUTHOR

Zak Seidov, May 27 2010

STATUS

approved

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Last modified September 26 14:21 EDT 2022. Contains 356999 sequences. (Running on oeis4.)