Sum of the square root of n-th square triangular number and n-th Pell (or lambda) number (A000129).

A113449

Sum of the square root of n-th square triangular number and n-th Pell (or lambda) number (A000129).

Terms

    a(0) =2a(1) =8a(2) =40a(3) =216a(4) =1218a(5) =7000a(6) =40560a(7) =235824a(8) =1373090a(9) =7999592a(10) =46616920a(11) =271683720a(12) =1583441442a(13) =9228858808a(14) =53789455200a(15) =313507253856

External references