Numbers k such that the centered triangular number A005448(k) = 3*k*(k-1)/2 + 1 is a perfect square.
A129444
Numbers k such that the centered triangular number A005448(k) = 3*k*(k-1)/2 + 1 is a perfect square.
Terms
- a(0) =0a(1) =1a(2) =2a(3) =7a(4) =16a(5) =65a(6) =154a(7) =639a(8) =1520a(9) =6321a(10) =15042a(11) =62567a(12) =148896a(13) =619345a(14) =1473914a(15) =6130879a(16) =14590240a(17) =60689441a(18) =144428482a(19) =600763527a(20) =1429694576a(21) =5946945825a(22) =14152517274a(23) =58868694719a(24) =140095478160a(25) =582740001361
External references
- oeis: A129444