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A226902 Numbers c such that the difference of consecutive cubes (c+1)^3 - c^3 is the sum of two positive cubes. 4
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The numbers c in A225909.

The sequence is infinite, because A226903 is a parametrized infinite subsequence.

LINKS

Chai Wah Wu, Table of n, a(n) for n = 1..5000

FORMULA

a(n) = (-3 + sqrt(9 + 12*(A225909(n) - 1)))/6

EXAMPLE

(5+1)^3 - 5^3 = 3^3 + 4^3, so 5 is a member.

CROSSREFS

Cf. A225909, A226903.

Sequence in context: A155086 A219049 A245534 * A026595 A037233 A197539

Adjacent sequences:  A226899 A226900 A226901 * A226903 A226904 A226905

KEYWORD

nonn

AUTHOR

Jonathan Sondow, Jun 21 2013

STATUS

approved

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Last modified June 27 21:39 EDT 2017. Contains 288804 sequences.