|
%I #12 Apr 03 2023 07:49:43
%S 5,7,8,9,12,17,18,19,21,22,23,24,25,28,31,32,33,35,37,38,39,41,42,44,
%T 45,46,47,51,52,53,54,55,57,59,60,61,63,65,66,67,68,69,70,71,72,73,74,
%U 75,77,78,79,80,81,82,83,84,85,87,88,89,90,91,93,95,96,97,98,99,100,101
%N Numbers whose square can be expressed as the sum of a square, a cube and a fourth power, all positive.
%C a(n)^2 = x^2 + y^3 + z^4 with x,y,z > 0.
%e a(5) = 12 is a term since 12*12 = 144 = 6^2 + 3^3 + 3^4 = 36 + 27 + 81.
%o (PARI) for(D=1,99,for(C=1,sqrtn(D^2-1,4),for(B=1,sqrtn(D^2-C^4-1,3),issquare(D^2-C^4-B^3,&A)&&print1([A,B,C,D][4]",")+next(3)))) \\ _M. F. Hasler_, Apr 06 2015
%Y Cf. A180242, A256091, A256613, A255830.
%K nonn
%O 1,1
%A _Carmine Suriano_, Aug 19 2010
|
