24031

Appears in sequences

• a(n) = (1/C(n,0) - 1/C(n,1) + ... + d/C(n,k))*L, where d = (-1)^k,k = [ n/2 ], L = LCM{C(n,0), C(n,1),..., C(n,n)}.at n=13A025536
• a(n) = A027082(n, 2n).at n=12A027087
• Numbers whose base-4 representation contains exactly four 1's and four 3's.at n=6A045133
• Expansion of (5 - 9*x + 6*x^2)/(1-x)^4.at n=41A080957
• Semiprimes in A003215.at n=38A113530
• Number of symmetric bushes with n edges. I.e., number of ordered trees with n edges, no non-root vertices of outdegree 1 and symmetrical with respect to the vertical axis passing through the root.at n=24A125189
• Numerator of the continued fraction convergents of the decimal concatenation of the Fibonacci numbers.at n=3A128871
• a(n)=a(n-1)+a(n-2)+a(n-3)+2a(n-4); a(0)=0,a(1)=1,a(2)=3,a(3)=7.at n=15A139814
• E.g.f. is reversion of (2(1+x)log(1+x)+x^2+2x)/( (2+x)^2(1+x) ).at n=5A140983
• a(n) = 3*n^4 + 6*n^3 - 3*n + 1.at n=9A181475
• Principal diagonal of the convolution array A213778.at n=40A213779
• Number of (n+2) X (2+2) 0..3 arrays with every 3 X 3 subblock row, column, diagonal and antidiagonal sum not equal to 0 3 4 6 or 7.at n=6A252133
• Number of (n+2)X(7+2) 0..3 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 3 4 6 or 7.at n=1A252138
• T(n,k)=Number of (n+2)X(k+2) 0..3 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 3 4 6 or 7.at n=29A252139
• T(n,k)=Number of (n+2)X(k+2) 0..3 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 3 4 6 or 7.at n=34A252139
• Odd numbers n such that the sum of the binary digits of n and n^2 both equal 12.at n=22A261593