269620

Appears in sequences

• Number of right triangles whose vertices are lattice points in {1,2,...,n} X {1,2,...,n}.at n=18A077435
• Non-palindromes whose squares are in A066531.at n=18A206642
• For every positive integer m, let u(m) = (d(1),d(2),...,d(k)) be the unitary divisors of m. The sequence (a(n)) consists of integers of the form d(k)/d(1) + d(k-1)/d(2) + ... + d(k)/d(1).at n=24A229999