25481

Appears in sequences

• a(n) = a(n-1) + 2*a(n-2) + (-1)^n.at n=15A006904
• a(n) = (10*n^3 - 9*n^2 + 2*n)/3 + 1.at n=20A034721
• Number of bracelet structures using exactly two different colored beads.at n=20A056357
• Composite numbers generated by the Euler polynomial x^2 + x + 41.at n=30A145292
• a(n) = smallest composite (odd) number greater than a(n-1) such that a(n)+2n is the first prime after a(n).at n=20A189118
• a(n) is the number of representative two-color bracelets (necklaces with turnover allowed) with n beads for n >= 2.at n=19A213942
• Semiprimes generated by the Euler polynomial x^2 + x + 41.at n=30A228183
• Number of partitions p of n such that 2*(number of even numbers in p) <= (number of odd numbers in p).at n=45A241652
• Number of necklaces with n beads colored white or red, where the number of white beads is odd and at least three and turning over is allowed.at n=18A263768
• G.f. A(x) satisfies: A(x - 4*x*A(x)) = x - 3*x*A(x).at n=5A291815
• Number of unlabeled rooted trees with n nodes in which the branches of any node with more than one distinct branch have empty intersection.at n=13A316501