0,2

a(n) = ((2n)^((2n+1)^2) + 1)/(2n+1)^3

Table[ ((2n)^((2n+1)^2) + 1)/(2n+1)^3, {n, 0, 10} ]

Cf. A137641 = ((n - 1)^(n^2) + 1)/n^3. Cf. A137642 = ((p + 1)^(p^2) - 1)/p^3 for p = prime[n]. Cf. A133591 = ((p - 1)^(p^2) + 1)/p^3 for p = prime[n].

Sequence in context: A013890 A128400 A133591 this_sequence A023921 A072840 A091234

Adjacent sequences: A137640 A137641 A137642 this_sequence A137644 A137645 A137646

nonn

Alexander Adamchuk (alex(AT)kolmogorov.com), Jan 31 2008