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A224485 Numbers which are the sum of two positive cubes and divisible by 5. 2
35, 65, 250, 280, 370, 520, 730, 855, 945, 1125, 1395, 1755, 2000, 2060, 2205, 2240, 2540, 2745, 2960, 3500, 3925, 4075, 4160, 4375, 4825, 4940, 5425, 5840, 6175, 6750, 6840, 6860, 7075, 7110, 7560, 8125, 8190, 9000, 9325, 9990 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

If 12*h-75 is a square then some values of 5*h are in this sequence. It is easy to verify that h is of the form 3*m^2-3*m+7, and therefore 5*(3*m^2-3*m+7) = (3-m)^3+(m+2)^3.

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

MATHEMATICA

Select[Union[Total/@(Tuples[Range[20], 2]^3)], Divisible[#, 5]&]

CROSSREFS

Cf. A224484 (divisible by k=3), A101421 (k=7), A101852 (k=11), A094447 (k=13), A099178 (k=17), A102619 (k=19), A101806 (k=23), A224483 (k=29), A102658 (k=31), A102618 (k=37).

Sequence in context: A108172 A176875 A162832 * A267330 A229357 A254364

Adjacent sequences:  A224482 A224483 A224484 * A224486 A224487 A224488

KEYWORD

nonn,easy

AUTHOR

Vincenzo Librandi, May 10 2013

STATUS

approved

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Last modified July 20 20:57 EDT 2017. Contains 289629 sequences.