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A162586
Integers n for which k = (7 * (256^n - 16^n) + n^2) / (n * (8n + 7)) is an integer
1
2, 3, 5, 8, 9, 12, 15, 18, 20, 24, 27, 32, 45, 54, 60, 75, 78, 80, 90, 102, 110, 120, 128, 135, 162, 165, 170, 180, 192, 195, 200, 234, 243, 275, 288, 312, 330, 333, 360, 384, 408, 432, 440, 450, 465, 480, 495, 500, 513, 540, 612, 620, 624, 675, 684, 702, 729
OFFSET
1,1
COMMENTS
8n + 7 is almost always prime. It is first composite for 8 * 372060 + 7 = 2976487 = 863 * 3449.
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Reikku Kulon, Jul 07 2009
STATUS
approved