25415

Appears in sequences

• Number of binary necklaces of length n with no subsequence 00, excluding the necklace "0".at n=27A000358
• Number of Dyck n-paths with ascents and descents of length equal to 1 (mod 4).at n=22A023427
• Sum of consecutive nonsquares.at n=23A048395
• T(n,k) = 5*A046802(n,k) - 4*A007318(n,k), triangle read by rows (0 <= k <= n).at n=31A168290
• T(n,k) = 5*A046802(n,k) - 4*A007318(n,k), triangle read by rows (0 <= k <= n).at n=32A168290
• G.f. satisfies: A(x) = (1 + x*A(x)) * (1 + x^4*A(x)).at n=21A216116
• Composite squarefree numbers n such that p(i)-9 divides n+9, where p(i) are the prime factors of n.at n=45A225709
• Number of (0, 1)-necklaces of length n without zigzags (see reference for precise definition).at n=28A263659
• a(n) = Sum_{1 <= x_1, x_2, x_3 <= n} gcd(x_1, n)/gcd(x_1, x_2, x_3, n).at n=19A373060
• Sum of the n-th maximal run of adjacent (increasing by one at a time) non-perfect-powers.at n=30A375705