A083081 First superdiagonal of number array A083075.

1, 13, 229, 4921, 128841, 4022341, 146450893, 6103787761, 286833509137, 15011892880381, 866190689012661, 54637591044108073, 3740820141248285785, 276304073198956644661, 21900911192388373534621

Offset

1,2

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..300

Formula

a(n) = ((n-1)*(2n+1)^n + 1)/n.

Prog

(Magma) [((n-1)*(2*n+1)^n+1)/n: n in [1..20]]; // Vincenzo Librandi, Nov 12 2011

Crossrefs

Cf. A083080, A083082.

Sequence in context: A223548 A201706 A176722 * A083306 A114755 A142610

Adjacent sequences: A083078 A083079 A083080 * A083082 A083083 A083084

Keyword

easy,nonn

Author

Paul Barry, Apr 23 2003

Status

approved