A233446 a(n) = ((2n-1)^(2n+1) + (2n+1)^(2n-1))/(2n)^2 = A154682(n)/(2n)^2 for n > 0.

1, 23, 2637, 705259, 337390073, 252186614847, 271082082053317, 396049017137512403, 754792662169555947633, 1818644980834260579498343, 5405067064522549127719680701, 19423396040054801221090342470843, 83016890560608261435356904433668457, 416213066932582983199004231480676255119, 2419095491735191624607023665166934072373813

Offset: 1

Author

Alexander Adamchuk, Dec 10 2013

Keywords

• nonn

Crossrefs

Cf. A154682.

Programs

Mathematica

Table[((2 n - 1)^(2 n + 1) + (2 n + 1)^(2 n - 1))/(2 n)^2, {n, 1, 15}]

Formula

a(n) = ((2n-1)^(2n+1) + (2n+1)^(2n-1))/(2n)^2; n > 0.