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A226902
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Numbers c such that the difference of consecutive cubes (c+1)^3 - c^3 is the sum of two positive cubes.
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4
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5, 8, 18, 40, 53, 70, 102, 114, 188, 197, 213, 248, 255, 297, 306, 453, 460, 477, 487, 491, 495, 564, 632, 671, 684, 768, 909, 958, 989, 1190, 1290, 1324, 1331, 1346, 1744, 1745, 1779, 2068, 2130, 2178, 2208, 2262, 2448, 2790, 2813, 3320, 3327, 3402, 3414
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OFFSET
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1,1
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COMMENTS
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The sequence is infinite, because A226903 is a parametrized infinite subsequence.
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LINKS
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FORMULA
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a(n) = (-3 + sqrt(9 + 12*(A225909(n) - 1)))/6
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EXAMPLE
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(5+1)^3 - 5^3 = 3^3 + 4^3, so 5 is a member.
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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