A083081 First superdiagonal of number array A083075.
1, 13, 229, 4921, 128841, 4022341, 146450893, 6103787761, 286833509137, 15011892880381, 866190689012661, 54637591044108073, 3740820141248285785, 276304073198956644661, 21900911192388373534621
Offset: 1
Links
- Vincenzo Librandi, Table of n, a(n) for n = 1..300
Programs
-
Magma
[((n-1)*(2*n+1)^n+1)/n: n in [1..20]]; // Vincenzo Librandi, Nov 12 2011
Formula
a(n) = ((n-1)*(2n+1)^n + 1)/n.