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A110228
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4-almost primes p * q * r * s not relatively prime to p + q + r + s.
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11
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16, 24, 36, 60, 81, 84, 100, 126, 132, 140, 150, 156, 196, 204, 220, 228, 234, 260, 276, 308, 315, 330, 340, 342, 348, 364, 372, 375, 380, 444, 460, 476, 484, 490, 492, 495, 510, 516, 525, 532, 558, 564, 572, 580, 585, 620, 625, 636, 644, 650, 666, 676, 690
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| p, q, r, s are not necessarily distinct. The converse to this is A110227: 4-almost primes p * q * r * s which are relatively prime to p+q+r+s.
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EXAMPLE
| 84 is in this sequence because 84 = 2^2 * 3 * 7 and the sum of these prime factors is 2 + 2 + 3 + 7 = 14 = 2 * 7, which is a divisor of 84.
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CROSSREFS
| Cf. A014613, A110187, A110188, A110227, A110229, A110230, A110231, A110232, A110289, A110290, A110296, A110297.
Sequence in context: A103248 A140135 A120142 * A175161 A045875 A046434
Adjacent sequences: A110225 A110226 A110227 * A110229 A110230 A110231
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KEYWORD
| easy,nonn
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AUTHOR
| Jonathan Vos Post (jvospost3(AT)gmail.com), Jul 16 2005
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EXTENSIONS
| Corrected and extended by Ray Chandler (rayjchandler(AT)sbcglobal.net), Jul 20 2005
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