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A099178
Numbers which are the sum of two positive cubes and divisible by 17.
7
1241, 1343, 1547, 1853, 2261, 2771, 3383, 4097, 9826, 9928, 10234, 10744, 11458, 12376, 13498, 14824, 16354, 18088, 20026, 22168, 24514, 27064, 29818, 32776, 33201, 33507, 34119, 35037, 35938, 36261, 37791, 39627, 41769, 44217, 46971
OFFSET
1,1
LINKS
EXAMPLE
Sums not divisible by 17 are indicated in asterisks:
....|...1....8...27...64...125...216...343...512...729..1000..1331
------------------------------------------------------------------
1...|...*....*....*....*.....*.....*.....*.....*.....*.....*.....*
8...|...*....*....*....*.....*.....*.....*.....*.....*.....*.....*
27..|...*....*....*....*.....*.....*.....*.....*.....*.....*.....*
64..|...*....*....*....*.....*.....*.....*.....*.....*.....*.....*
125.|...*....*....*....*.....*.....*.....*.....*.....*.....*.....*
216.|...*....*....*....*.....*.....*.....*.....*.....*.....*..1547
343.|...*....*....*....*.....*.....*.....*.....*.....*..1343.....*
512.|...*....*....*....*.....*.....*.....*.....*...1241....*.....*
729.|...*....*....*....*.....*.....*.....*..1241.....*.....*.....*
1000|...*....*....*....*.....*.....*..1343.....*.....*.....*.....*
1331|...*....*....*....*.....*..1547.....*.....*.....*.....*.....*
MATHEMATICA
upto[n_] := Block[{t}, Union@ Reap[ Do[If[Mod[t = x^3 + y^3, 17] == 0, Sow@t], {x, n^(1/3)}, {y, Min[x, (n - x^3)^(1/3)]}]][[2, 1]]]; upto[47000] (* Giovanni Resta, Jun 12 2020 *)
CROSSREFS
Cf. A098365.
Sequence in context: A237552 A010081 A028514 * A209711 A228964 A047628
KEYWORD
nonn,easy
AUTHOR
Jun Mizuki (suzuki32(AT)sanken.osaka-u.ac.jp), Nov 15 2004
STATUS
approved