40656

Appears in sequences

• Expansion of 1/((1-2x)(1-3x)(1-7x)).at n=5A016276
• Expansion of 1/((1-2x)(1-8x)(1-10x)).at n=4A016317
• a(n) = partitions(n)*partitions(n+1).at n=15A090982
• a(n) = 225*n^2 - 251*n + 70.at n=14A156810
• a(1) = 1, then partial products of Product_{n>=1} (p(n)/p(n-1)*p(n)/p(n-1)) = 1*1*1*(2)*(2)*(3/2)*(3/2)*(5/3)*(5/3)*(7/5)*(7/5)*...*; p = partition numbers, A000041 starting (1, 2, 3, 5, ...).at n=31A171646
• Number of ways to place 2 nonattacking knights on an n X n board.at n=16A172132
• Number of 4-step self-avoiding walks on an n X n square summed over all starting positions.at n=34A188149
• Area A of the triangles such that A, the sides and one of the altitudes are four consecutive integers of an arithmetic progression d.at n=21A210645
• Triangle read by rows: T(n,k) = logarithmic polynomial A_k^(n)(x) evaluated at x=-1.at n=39A260325
• Square array A(row,col) = Sum_{k=0..row} binomial(row,k)*A002110(col+k), read by descending antidiagonals as A(0,0), A(0,1), A(1,0), A(0,2), A(1,1), A(2,0), ...at n=25A276586
• Transpose of square array A276586.at n=23A276587
• Expansion of r(q)^4 / r(q^4) in powers of q where r() is the Rogers-Ramanujan continued fraction.at n=42A285629
• Expansion of e.g.f. exp(x^3 * exp(x)).at n=8A292889
• a(n) = n^2*(2*n - 3 - (-1)^n)/4.at n=43A303692
• a(n) = lcm(sigma(n), pod(n)) / n, where sigma (k) = the sum of divisors of k (A000203) and pod(n) = the product of divisors of k (A007955).at n=43A307893
• Triangle T(n, k) = Sum_{i=1..n} Stirling2(n,i) * abs(Stirling1(i-1,k-1)), n >= 1, 1 <= k <= n.at n=51A320280
• Number of 2 X 2 matrices over Z_n whose permanent equals their determinant.at n=21A345754
• a(n) = n! * Sum_{k=0..floor((n-1)/4)} 1 / (4*k+1)!.at n=8A349089
• a(n) is the number of iterations of the computation of the A351849 tag system when started from the word encoding n, or -1 if the number of iterations is infinite.at n=26A351850
• Triangle read by rows: T(n,k) is the number of n X n Boolean matrices with Schein rank k, 0 <= k <= n.at n=13A355333