The index of the first of two consecutive positive triangular numbers (A000217) the sum of which is equal to the sum of four consecutive positive triangular numbers.
A262490
The index of the first of two consecutive positive triangular numbers (A000217) the sum of which is equal to the sum of four consecutive positive triangular numbers.
Terms
- a(0) =9a(1) =57a(2) =337a(3) =1969a(4) =11481a(5) =66921a(6) =390049a(7) =2273377a(8) =13250217a(9) =77227929a(10) =450117361a(11) =2623476241a(12) =15290740089a(13) =89120964297a(14) =519435045697
External references
- oeis: A262490