131028

Appears in sequences

• a(n) = |{m : multiplicative order of 7 mod m=n}|.at n=47A059889
• Total number of parts that are neither the smallest part nor the largest part in all partitions of n.at n=38A182977
• a(n) is the minimum integer k such that the smallest prime factor of the n-th Fermat number exceeds 2^(2^n - k).at n=17A358684