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A230353 Products of 3 evil primes (A027699) p,q,r, such that numbers p*q, p*r, q*r,  and p*q*r are odious (A000069). 2
575, 1775, 2075, 2225, 2825, 3475, 6575, 8381, 8675, 8825, 8975, 8993, 10235, 11225, 11675, 11975, 12035, 12167, 12905, 13075, 14275, 14825, 18745, 19925, 21575, 22881, 23943, 24389, 25325, 25775, 26765, 27575, 30189, 30925, 30981, 31433, 32223, 32675, 32975 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

These numbers are products of 3 evil numbers (A001969) but not represented as products of two evil numbers (A230213).

LINKS

Charles R Greathouse IV and Peter J. C. Moses, Table of n, a(n) for n = 1..10000 (first 500 from Moses)

EXAMPLE

For triple of evil primes {3,29,263} numbers 3*29 = 87, 3*263 = 789, 29*263 = 7627 and 3*29*263 = 22881. Thus 22881 is in the sequence.

PROG

(PARI) od(n)=hammingweight(n)%2

list(lim)=my(v=List(), pq); forprime(p=23, lim\25, if(od(p), next); forprime(q=5, min(lim\(3*p), p), if(od(q) || !od(pq=p*q), next); forprime(r=3, min(lim\pq, q), if(!od(r) && od(q*r) && od(p*r) && od(pq*r), listput(v, pq*r))))); vecsort(Vec(v)) \\ Charles R Greathouse IV, Nov 01 2013

CROSSREFS

Cf. A000069, A001969, A027699, A230213.

Sequence in context: A291133 A027456 A158372 * A233482 A027527 A069421

Adjacent sequences:  A230350 A230351 A230352 * A230354 A230355 A230356

KEYWORD

nonn,base

AUTHOR

Vladimir Shevelev and Peter J. C. Moses, Oct 16 2013

STATUS

approved

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Last modified August 8 02:45 EDT 2020. Contains 336290 sequences. (Running on oeis4.)