0,3

36m^2+36m+11=(6m+3)^2+2, i.e. two more than the square of odd multiples of 3. 36m^2+36m+11=72*(m*(m+1)/2)+11, i.e. eleven more than seventy-two times triangular numbers.

a(n) =A002024((A056899(n+2)-11)/72)

a(3)=3 because 36*3^2+36*3+11=443 which is prime

This sequence (with the formula above) generates all except the first two terms of the sequence of primes of the form k^2+2, A056899.

Sequence in context: A153763 A050747 A074780 this_sequence A096594 A100693 A030159

Adjacent sequences: A056897 A056898 A056899 this_sequence A056901 A056902 A056903

nonn

Henry Bottomley (se16(AT)btinternet.com), Jul 05 2000