Values of k such that 2*k+1 and 5*k+1 are both triangular numbers.
A274579
Values of k such that 2*k+1 and 5*k+1 are both triangular numbers.
Terms
- a(0) =0a(1) =1a(2) =7a(3) =27a(4) =540a(5) =2002a(6) =10660a(7) =39501a(8) =779247a(9) =2887450a(10) =15372280a(11) =56960982a(12) =1123674201a(13) =4163701465a(14) =22166817667a(15) =82137697110
External references
- oeis: A274579