cp's OEIS Frontend

A099178 Numbers which are the sum of two positive cubes and divisible by 17.

%I A099178 #9 Jun 13 2020 02:39:34
%S A099178 1241,1343,1547,1853,2261,2771,3383,4097,9826,9928,10234,10744,11458,
%T A099178 12376,13498,14824,16354,18088,20026,22168,24514,27064,29818,32776,
%U A099178 33201,33507,34119,35037,35938,36261,37791,39627,41769,44217,46971
%N A099178 Numbers which are the sum of two positive cubes and divisible by 17.
%H A099178 Vincenzo Librandi, <a href="/A099178/b099178.txt">Table of n, a(n) for n = 1..1000</a>
%e A099178 Sums not divisible by 17 are indicated in asterisks:
%e A099178 ....|...1....8...27...64...125...216...343...512...729..1000..1331
%e A099178 ------------------------------------------------------------------
%e A099178 1...|...*....*....*....*.....*.....*.....*.....*.....*.....*.....*
%e A099178 8...|...*....*....*....*.....*.....*.....*.....*.....*.....*.....*
%e A099178 27..|...*....*....*....*.....*.....*.....*.....*.....*.....*.....*
%e A099178 64..|...*....*....*....*.....*.....*.....*.....*.....*.....*.....*
%e A099178 125.|...*....*....*....*.....*.....*.....*.....*.....*.....*.....*
%e A099178 216.|...*....*....*....*.....*.....*.....*.....*.....*.....*..1547
%e A099178 343.|...*....*....*....*.....*.....*.....*.....*.....*..1343.....*
%e A099178 512.|...*....*....*....*.....*.....*.....*.....*...1241....*.....*
%e A099178 729.|...*....*....*....*.....*.....*.....*..1241.....*.....*.....*
%e A099178 1000|...*....*....*....*.....*.....*..1343.....*.....*.....*.....*
%e A099178 1331|...*....*....*....*.....*..1547.....*.....*.....*.....*.....*
%t A099178 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 *)
%Y A099178 Cf. A098365.
%K A099178 nonn,easy
%O A099178 1,1
%A A099178 Jun Mizuki (suzuki32(AT)sanken.osaka-u.ac.jp), Nov 15 2004