323554domain: NAppears in sequencesAlkane (or paraffin) numbers l(13,n).at n=12A018214Number of bracelets (turn over necklaces) with n beads: 1 blue, 12 green, and r = n - 13 red.at n=10A141783Number of n-element subsets of [n+10] having an even sum.at n=12A282086a(n) = Sum_{k=1..n} sigma_2( (n/gcd(k,n))^2 ).at n=13A372996