20946

Appears in sequences

• Number of inequivalent ways (mod D_4) a pair of checkers can be placed on an n X n board.at n=23A014409
• Number of partitions satisfying cn(0,5) <= cn(1,5) + cn(4,5) + cn(2,5) and cn(0,5) <= cn(1,5) + cn(4,5) + cn(3,5).at n=37A039844
• Values of m such that N=(am+1)(bm+1)(cm+1) is a 3-Carmichael number (A087788), where a,b,c = 1,2,21.at n=26A064247
• Values of n such that N=(an+1)(bn+1)(cn+1) is a 3-Carmichael number (A087788), where a,b,c = 1,2,35.at n=11A064254
• Let p = n-th irregular prime, A000928(n). Then a(n) = smallest value of m such that numerator(Bernoulli(2*m)/(2*m)) / numerator(Bernoulli(2*m)/(2*m*(2*m-1))) equals p.at n=9A092291
• a(n) = number of ways to dispose two pawns on a chessboard of size n X n (two dispositions are equivalent if one can be rotated or reflected to give the other one).at n=24A141582
• a(n) = 121*n^2 - 204*n + 86.at n=13A157440
• The numbers n in s=n^2 + (n+1)^2 that satisfy the requirement for two consecutive squares c,d with c<d with d-c being the sum of two consecutive squares that c<s<d will give s-c and d-s both being squares.at n=22A192743
• Number of (n+5)X1 arrays of occupancy after each element moves up to +-5 places but not 0 and without 2-loops.at n=3A222163
• T(n,k)=Number of length (n+k)X1 arrays of occupancy after each element moves up to +-k places but not 0 and without 2-loops.at n=31A222165
• Number T(m,n) of series-reduced free trees with n nodes of which exactly m >= 3 are leaves, m+1 <= n <= 2m-2.at n=100A271205
• Irregular triangle read by rows: T(n,k) is the number of free polyominoes with n cells having k regions between the polyominoes and their bounding boxes, n >= 1, k >= 0.at n=53A380282