102280151421
domain: N
Appears in sequences
- Lerch's function q_2(n) = (2^{phi(t)} - 1)/t where t = 2*n - 1.at n=21A001226
- Fermat quotients: (2^(p-1)-1)/p, where p=prime(n).at n=12A007663
- Number of cycles of length n under the mapping x -> x^2-2 modulo Fermat prime 2^(2^m)+1, where m is any fixed integer such that n divides 2^m-1.at n=21A131203
- a(n) = floor((1 + 4^n)/(1 + 2*n)).at n=20A191637
- Carmichael quotients to base 2: a(n) = (2^lambda(2*n-1)-1)/(2*n-1), where lambda is the Carmichael lambda function (A002322).at n=21A329238