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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
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
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