A199692 Subsequence of Pythagorean primes (A002144): each square is used only once.
5, 41, 73, 149, 157, 277, 313, 613, 617, 709, 929, 1117, 1201, 1741, 1753, 1873, 2381, 2897, 2969, 3469, 3613, 3637, 3697, 4513, 4597, 5101, 5953, 6173, 6857, 6869, 7577, 8089, 8581, 9661, 10369, 10513, 11717, 12097, 12653, 12973, 13001, 13649, 14461, 15313
Offset: 1
Keywords
Examples
First Pythagorean prime A002144(1)=5=1+4, "uses" squares 1^2 and 2^2. Next Pythagorean prime which does not "use" 1^2 and 2^2 is A002144(6)=41=4^2+5^2, hence a(2)=41. Next Pythagorean prime which does not "use" 1^2, 2^2, 4^2 and 5^2 is A002144(9)=73=3^2+8^2, hence a(3)=73. Next Pythagorean prime which does not "use" 1^2, 2^2, 3^2, 4^2, 5^2 and 8^2 is A002144(16)=149=7^2+10^2, hence a(4)=149.
Links
- Zak Seidov, Table of n, a(n) for n = 1..2000
Crossrefs
Cf. A002144.