21432

Appears in sequences

• Number of possible queen moves on an n X n chessboard.at n=18A035005
• Numbers k such that k!!!!!! - 1 is prime.at n=17A051592
• Triangle read by rows: T(n,k) is the number of even permutations of {1,2,...,n} with no fixed points and having k excedances (n>=1; k>=1).at n=39A145881
• Triangle read by rows: T(n,k) is the number of even permutations of {1,2,...,n} with no fixed points and having k excedances (n>=1; k>=1).at n=43A145881
• a(n) = -4*a(n-1) + 6*a(n-2) for n > 1 with a(0) = 1 and a(1) = -6.at n=6A152223
• a(n)=4*a(n-1)+6*a(n-2), n>1 ; a(0)=1, a(1)=6 .at n=6A152224
• Number of (n+1)X(2+1) 0..3 arrays with every 2X2 subblock having the sum of the absolute values of the edge differences equal to 6 and no adjacent elements equal.at n=3A233727
• Number of (n+1)X(4+1) 0..3 arrays with every 2X2 subblock having the sum of the absolute values of the edge differences equal to 6 and no adjacent elements equal.at n=1A233729
• T(n,k)=Number of (n+1)X(k+1) 0..3 arrays with every 2X2 subblock having the sum of the absolute values of the edge differences equal to 6 and no adjacent elements equal.at n=11A233733
• T(n,k)=Number of (n+1)X(k+1) 0..3 arrays with every 2X2 subblock having the sum of the absolute values of the edge differences equal to 6 and no adjacent elements equal.at n=13A233733
• The number of tilings of an equilateral triangle of side length n with k lozenges and n^2 - 2*k unit triangles. Triangle T(n, k) with n >= 1 and 0 <= k <= n*(n + 1)/2, read by rows.at n=23A273464
• a(n) = (1/6)*A290911(n).at n=8A290912
• a(n) = 82*2^n + 440.at n=8A305268
• G.f.: Sum_{k>=0} x^(2^k) / Product_{j=1..2^k} (1 - x^j).at n=49A339447
• Let G be a simple labeled graph with vertex set [n] and let P be a set partition of [n]. Then a(n) is the number of ordered pairs (G,P) such that for all x,y in [n], if x and y are in the same block of P then there is a path in G from x to y.at n=4A371126
• Number of polycubes of size n and symmetry class C.at n=13A376967