21879

Appears in sequences

• Number of n-bead bracelets (turnover necklaces) with 8 red beads and n-8 black beads.at n=17A005514
• Euler transform of Thue-Morse sequence A001285.at n=25A029877
• Number of nonempty subsets of {1,2,...,n} in which exactly 1/6 of the elements are <= (n-4)/2.at n=21A048069
• (Terms in A014476)/2.at n=38A051497
• Maximal value of products of partitions of n into powers of distinct primes (powers of 1 and 2 excluded).at n=50A051704
• Linear recursion with Catalan numbers.at n=7A053369
• Product of terms in row n of A082817.at n=3A082820
• Row sums of A095167.at n=33A095170
• Table of denominators of coefficients of certain rational polynomials.at n=63A101023
• a(n) = n*(n+1)*(n+2)*(n+3)*(n+4)*(2 + 4*n + n^2)/840.at n=8A101097
• Largest order of a permutation of n elements with exactly 4 cycles. Also the largest LCM of a 4-partition of n.at n=49A129649
• Number of sets (in the Hausdorff metric geometry) at each location between two sets defining a polygonal configuration consisting of two 4-gonal polygonal components chained with string components of length l as l varies.at n=11A152929
• G.f.: 1 / ( (1 + x^2 - x^3)^2 * (1 - x - 2*x^2 - x^3) ).at n=14A218438
• a(n) = A239793(n)/2^(3*n).at n=25A239795
• Triangle read by rows, T(n,k) = denominator(binomial(-1/2, n-k))*binomial(n-1/2, k-1/2), for n>=0 and 0<=k<=n.at n=49A269949
• Triangle read by rows, T(n,k) = denominator(binomial(1/2,n-k))*binomial(n+1/2, k+1/2), for n>=0 and 0<=k<=n.at n=39A269950
• Numerators of coefficient triangle for expansion of x^(2*n) in terms of Chebyshev polynomials of the first kind T(2*m, x) (A127674).at n=46A273167
• Numerators of coefficient triangle for integrated even powers of cos(x) in terms of x and sin(2*m*x).at n=46A273169
• Numbers which are palindromic in their Elias delta code representation.at n=42A281380
• a(n) = Catalan(n)*Motzkin(n-1).at n=6A290443