20066

Appears in sequences

• Number of ways to place a non-attacking white and black pawn on n X n chessboard.at n=12A035290
• Numbers k such that 4^k == 2 (mod k).at n=4A130421
• Number of nX4 binary arrays with each sum of a(1..i,1..j) no greater than i*j/2 and rows and columns in nondecreasing order.at n=6A183411
• T(n,k)=Number of nXk binary arrays with each sum of a(1..i,1..j) no greater than i*j/2 and rows and columns in nondecreasing order.at n=48A183413
• T(n,k)=Number of nXk binary arrays with each sum of a(1..i,1..j) no greater than i*j/2 and rows and columns in nondecreasing order.at n=51A183413
• Floor(sqrt(3*2^n)).at n=27A221718
• Numbers n for which n = sigma*(x) = sigma*(y), where n = x + y and sigma*(n) is the sum of the anti-divisors of n.at n=3A227977
• Numbers k such that (83*10^k - 29) / 9 is prime.at n=22A278418
• Partial sums of A299277.at n=27A299278
• a(n) = A115004(2n)/4.at n=12A331760
• Even numbers k such that 2^(2*k) == 2 (mod k).at n=3A347908