119889

Appears in sequences

• Number of ordered 5-tuples of integers from [ 2,n ] with no common factors among quadruples.at n=26A015655
• Numerator of the fraction tan( Sum_{k=1..n} arctan(k) ).at n=13A180657
• Number of nonnegative integer matrices with total sum n, distinct columns with equal sums and any number of nonzero rows in nonincreasing lexicographic order.at n=11A330158
• a(0) = 1; thereafter a(n) = 2^(prime(n)-1) + Sum_{k=1..n} 2^(prime(n)-prime(k)).at n=7A333392