a(n) = (A000364(n+2)-A000364(n))/60.A081731a(n) = (A000364(n+2)-A000364(n))/60.Terms a(0) =1a(1) =23a(2) =841a(3) =45023a(4) =3321841a(5) =323146823a(6) =40078005241External referencesoeis: A081731