20392

Appears in sequences

• a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n+1-k), where k = [ (n+1)/2 ], s = (Lucas numbers), t = (composite numbers).at n=23A024471
• a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (Lucas numbers), t = (composite numbers).at n=22A025091
• Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 71.at n=32A031569
• One half of the number of non-self-conjugate balanced partitions.at n=59A067772
• Number of permutations of 1..n with all differences of elements separated by distances 1 through 7 being respectively unique.at n=17A170813
• Number of non-equivalent (mod D_3) ways to choose three points in an n X n X n triangular grid so that they do not form a 2 X 2 X 2 subtriangle.at n=11A237530