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A110229 5-almost primes p * q * r * s * t relatively prime to p + q + r + s + t. 12
48, 80, 108, 112, 176, 208, 252, 272, 300, 304, 368, 405, 420, 464, 468, 496, 500, 567, 592, 656, 660, 675, 684, 688, 752, 848, 891, 924, 944, 976, 980, 1020, 1053, 1072, 1116, 1136, 1140, 1168, 1264, 1300, 1323, 1328, 1332, 1372, 1377, 1424, 1428, 1452 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

p, q, r, s, t are not necessarily distinct. The converse to this is A110230: 5-almost primes p * q * r * s * t which are not relatively prime to p+q+r+s+t. A014614 is the 5-almost primes.

LINKS

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

EXAMPLE

48 is in this sequence because 48 = 2^4 * 3, which has no factors in common with 2 + 2 + 2 + 2 + 3 = 11.

PROG

(PARI) list(lim)=my(v=List()); forprime(p=2, lim\16, forprime(q=2, min(p, lim\8\p), my(pq=p*q); forprime(r=2, min(lim\pq\4, q), my(pqr=pq*r); forprime(s=2, min(lim\pqr\2, r), my(pqrs=pqr*s, n); forprime(t=2, min(lim\pqrs, s), n=pqrs*t; if(gcd(n, p+q+r+s+t)==1, listput(v, n))))))); Set(v) \\ Charles R Greathouse IV, Jan 31 2017

CROSSREFS

Cf. A014614, A002033, A110187, A110188, A110227, A110228, A110230, A110231, A110232, A110289, A110290, A110296, A110297.

Sequence in context: A260370 A260363 A261553 * A108608 A030628 A178739

Adjacent sequences:  A110226 A110227 A110228 * A110230 A110231 A110232

KEYWORD

easy,nonn

AUTHOR

Jonathan Vos Post, Jul 17 2005

EXTENSIONS

Extended by Ray Chandler, Jul 20 2005

Incorrect formula and comment of Sep 2009 related to A002033 deleted - R. J. Mathar, Oct 14 2009

STATUS

approved

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Last modified November 17 05:27 EST 2019. Contains 329217 sequences. (Running on oeis4.)