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A110227 4-almost primes p * q * r * s relatively prime to p + q + r + s. 11
40, 54, 56, 88, 90, 104, 135, 136, 152, 184, 189, 198, 210, 225, 232, 248, 250, 294, 296, 297, 306, 328, 344, 350, 351, 376, 390, 414, 424, 441, 459, 462, 472, 488, 513, 522, 536, 546, 550, 568, 570, 584, 621, 632, 664, 686, 712, 714, 735, 738, 765, 776 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

p, q, r, s are not necessarily distinct. The converse to this is A110228: 4-almost primes p * q * r * s not relatively prime to p+q+r+s.

EXAMPLE

104 is in this sequence because 104 = 2^3 * 13, which is relatively prime to 2 + 2 + 2 + 13 = 19, which is prime.

CROSSREFS

Cf. A014613, A110187, A110188, A110228, A110229, A110230, A110231, A110232, A110289, A110290, A110296, A110297.

Sequence in context: A167311 A039523 A116299 * A108607 A109730 A100333

Adjacent sequences:  A110224 A110225 A110226 * A110228 A110229 A110230

KEYWORD

easy,nonn

AUTHOR

Jonathan Vos Post (jvospost3(AT)gmail.com), Jul 16 2005

EXTENSIONS

Corrected and extended by Ray Chandler (rayjchandler(AT)sbcglobal.net), Jul 20 2005

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Last modified February 14 13:08 EST 2012. Contains 205623 sequences.