Numbers n such that the sum of the pentagonal numbers P(n) and P(n+1) is equal to the sum of the hexagonal numbers H(m) and H(m+1) for some m.
A251991
Numbers n such that the sum of the pentagonal numbers P(n) and P(n+1) is equal to the sum of the hexagonal numbers H(m) and H(m+1) for some m.
Terms
- a(0) =60a(1) =11704a(2) =2270580a(3) =440480880a(4) =85451020204
External references
- oeis: A251991