Triangular numbers (A000217) whose arithmetic derivative (A003415) is also a triangular number.

A351130

Triangular numbers (A000217) whose arithmetic derivative (A003415) is also a triangular number.

Terms

    a(0) =0a(1) =1a(2) =3a(3) =21a(4) =351a(5) =43956a(6) =187578a(7) =246753a(8) =570846a(9) =1200475a(10) =4890628a(11) =15671601a(12) =83663580a(13) =442903203a(14) =3776109156a(15) =35358717628

External references