47448

Appears in sequences

• Given a set of positive integers A={1,2,...,n-1,n}, n>=2. Take subsets of A of the form {1,...,n} so only subsets containing numbers 1 and n are allowed. Then a(1)=1 and a(n) is the number of subsets where arithmetic mean of the subset is an integer.at n=20A147980
• Records in A031883 (positions).at n=14A171924
• Number of 6-bead necklaces labeled with numbers -n..n allowing reversal, with sum zero and first and second differences in -n..n.at n=15A208973
• Number of binary arrays of length n+11 with fewer than 6 ones in any length 12 subsequence (=less than 50% duty cycle).at n=6A213116
• Number of binary arrays of length 2*n+6 with fewer than n ones in any length 2n subsequence (=less than 50% duty cycle).at n=5A213124
• a(n) = 2^n + 3^n + 6^n - 1.at n=5A330170