# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a110297 Showing 1-1 of 1 %I A110297 #9 Feb 01 2017 09:09:15 %S A110297 256,576,896,960,1296,1344,1440,1600,1944,2112,2160,2240,2496,2916, %T A110297 3024,3136,3168,3264,3360,3520,3600,3648,4000,4160,4416,4704,4752, %U A110297 4860,4896,4928,5040,5400,5440,5568,5616,5824,5952,6000,6080,6561,6624,6804,7056 %N A110297 8-almost primes p*q*r*s*t*u*v*w not relatively prime to p+q+r+s+t+u+v+w. %C A110297 The primes p, q, r, s, t, u, v, w are not necessarily distinct. The 8-almost primes are A046310. The converse, A110296, is 8-almost primes p*q*r*s*t*u*v*w which are relatively prime to p+q+r+s+t+u+v+w. %H A110297 Charles R Greathouse IV, Table of n, a(n) for n = 1..10000 %e A110297 576 = 2^6 * 3^2 is an element of this sequence because its sum of prime factors is 2 + 2 + 2 + 2 + 2 + 2 + 3 + 3 = 18 = 2 * 3^2 which is a factor of 576 and not relatively prime to 576. %o A110297 (PARI) list(lim)=my(v=List()); forprime(p=2, lim\128, forprime(q=2, min(p, lim\64\p), my(pq=p*q); forprime(r=2, min(lim\pq\32, q), my(pqr=pq*r); forprime(s=2, min(lim\pqr\16, r), my(pqrs=pqr*s); forprime(t=2, min(lim\pqrs\8, s), my(pqrst=pqrs*t); forprime(u=2, min(lim\pqrst\4, t), my(pqrstu=pqrst*u); forprime(w=2,min(lim\pqrstu\2,u), my(pqrstuw=pqrstu*w,n); forprime(x=2,min(lim\pqrstuw,w), n=pqrstuw*x; if(gcd(n, p+q+r+s+t+u+w+x)>1, listput(v, n)))))))))); Set(v) \\ _Charles R Greathouse IV_, Feb 01 2017 %Y A110297 Cf. A046310, A110187, A110188, A110227, A110228, A110229, A110230, A110231, A110232, A110289, A110290, A110296. %K A110297 easy,nonn %O A110297 1,1 %A A110297 _Jonathan Vos Post_, Jul 18 2005 %E A110297 Extended by _Ray Chandler_, Jul 20 2005 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE