cp's OEIS Frontend

A113490 Semiprimes a such that there exist three semiprimes b, c and d with a^3=b^3+c^3+d^3.

%I A113490 #7 Jul 11 2015 10:31:41
%S A113490 206,519,703,869,1418,1923,1945,2066,2095,2127,2446,2759,2867,2881,
%T A113490 2901,2913,2974,3099,3155,3207,3383,3398,3545,3649,3777,3814,3898,
%U A113490 4435,4766,4778,4873,4963,5091,5105,5165,5534,5582,5638,5771,5834,5855,6033,6098
%N A113490 Semiprimes a such that there exist three semiprimes b, c and d with a^3=b^3+c^3+d^3.
%C A113490 This is the semiprime analog of A114923.
%C A113490 There are only two such semiprimes < 10^4 with more than one solution: 2095 and 9897.
%e A113490 206^3 = 35^3 + 77^3 + 202^3.
%e A113490 519^3 = 4^3 + 303^3 + 482^3
%e A113490 703^3 = 111^3 + 291^3 + 685^3.
%e A113490 869^3 = 466^3 + 629^3 + 674^3.
%e A113490 2095^3 = 339^3 + 753^3 + 2059^3 = 543^3 + 1119^3 + 1969^3 (two ways).
%e A113490 9897^3 = 537^3 + 1454^3 + 9886^3 = 2071^3 + 3183^3 + 9755^3 (two ways).
%e A113490 Each of these numbers (other than the exponent 3) is a semiprime (A001358).
%Y A113490 Cf. A001358, A114923.
%K A113490 nonn
%O A113490 1,1
%A A113490 _Jonathan Vos Post_, Jan 09 2006
%E A113490 Extended by _Ray Chandler_, Jan 20 2006