A269840 Lesser of twin primes where both are the sum of 3 nonzero squares.

17, 41, 59, 107, 137, 179, 227, 281, 347, 419, 521, 569, 617, 641, 659, 809, 827, 857, 881, 1019, 1049, 1091, 1289, 1427, 1451, 1481, 1619, 1667, 1697, 1721, 1787, 1931, 2027, 2081, 2129, 2267, 2339, 2657, 2729, 2801, 2969, 3251, 3257, 3299, 3329, 3371, 3467, 3539

Offset: 1

Author

Altug Alkan, Mar 13 2016

Keywords

• nonn

Examples

			17 is a term because 17 = 2^2 + 2^2 + 3^2 and 19 = 1^2 + 3^2 + 3^2.
41 is a term because 41 = 3^2 + 4^2 + 4^2 and 43 = 3^2 + 3^2 + 5^2.
59 is a term because 59 = 3^2 + 5^2 + 5^2 and 61 = 3^2 + 4^2 + 6^2.
		

Links

• Chai Wah Wu, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A000408, A001359, A085317.

Programs

PARI

isA000408(n) = my(a, b) ; a=1 ; while(a^2+10, ); p-2}
for(n=1, 1e2, if(isA000408(t(n)) && isA000408(t(n)+2), print1(t(n), ", ")));