1048584

Appears in sequences

• Number of ways of 4-coloring a map in which there is a central circle surrounded by an annulus divided into n-1 regions. There are n regions in all.at n=15A090860
• Number of additive cyclic codes over GF(4) of length n that can be generated by one codeword.at n=18A143696
• a(n) = 8*(2^n + 1).at n=17A175161
• a(n) = 2^x+2^y where p(n) is the n-th prime of the form 4*k+1 and x, y is the unique integer solution to p(n) = x^2+y^2.at n=38A226640
• a(n) = 2^n + 8.at n=20A242475