A173957 Numbers n such that x^2+y^2+prime(n)^2=3*x*y*prime(n).
1, 3, 6, 10, 24, 51, 84, 251, 419, 755, 960, 3121, 3582, 4515, 9299, 35878, 42613, 127165, 211625, 235352, 5457937, 17353542, 23023556
Offset: 1
Keywords
Examples
a(1)=1 because 1^2+5^2+prime(1)^2=3*1*5*prime(1); a(2)=3 because 1^2+2^2+prime(3)^2=3*1*2*prime(3); a(3)=6 because 29^2+34^2+prime(6)^2=3*29*34*prime(6); a(4)=10 because 13^2+34^2=prime(10)^2=3*13*34*prime(10).
Formula
Extensions
Extended beyond 960 by R. J. Mathar, Mar 09 2010