78336

Appears in sequences

• Number of invertible 2 X 2 matrices mod n.at n=16A000252
• Number of 2 X 2 matrices with entries mod n and nonzero determinant.at n=16A005353
• a(n) = n*(n-1)*(n-2)^2.at n=16A047927
• Orders of the finite groups GL_2(K) when K is a finite field with q = A246655(n) elements.at n=10A059238
• Consider a Pythagorean triangle with sides a=u^2-v^2, b=2uv, c=u^2+v^2. The sequence is the area of the triangle when v=2, u=3,4,5,...at n=31A096382
• Expansion of (1+2*x-4*x^2)/((2*x+1)*(2*x-1)*(4*x^2+4*x-1)).at n=7A110047
• Number of 1:2:sqrt(5) proportioned triangles on an (n+1) X (n+1) grid.at n=20A190099
• Number of n X 5 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 1 and 1 0 1 vertically.at n=11A207450
• Number of the Lipschitz quaternions in a reduced system modulo n.at n=16A227499
• Number of n X 4 0..5 arrays with no element x(i,j) adjacent to itself or value 5-x(i,j) horizontally, diagonally or antidiagonally, top left element zero, and 1 appearing before 2 3 and 4, and 2 appearing before 3 in row major order (unlabeled 6-colorings with no clashing color pairs).at n=2A233170
• T(n,k)=Number of nXk 0..5 arrays with no element x(i,j) adjacent to itself or value 5-x(i,j) horizontally, diagonally or antidiagonally, top left element zero, and 1 appearing before 2 3 and 4, and 2 appearing before 3 in row major order (unlabelled 6-colorings with no clashing color pairs).at n=17A233174
• Number of 3 X n 0..5 arrays with no element x(i,j) adjacent to itself or value 5-x(i,j) horizontally, diagonally or antidiagonally, top left element zero, and 1 appearing before 2 3 and 4, and 2 appearing before 3 in row major order (unlabelled 6-colorings with no clashing color pairs).at n=3A233176
• Order of GL_2(p), the general linear group over F_p, where p runs through the primes.at n=6A244509
• Numerators of a sequence defined by a modified recurrence for the exponential of the von Mangoldt function.at n=33A277439
• Square array read by antidiagonals downwards: T(k,n) = sum of the site-perimeters of words of length n >= 1 over an alphabet of size k >= 1.at n=39A292767
• Order of the finite groups GL(m,q) [or GL_m(q)] in increasing order as q runs through the prime powers.at n=13A335384
• Orders of the finite groups Aut(GL_2(K)) when K is a finite field with q = A246655(n) elements.at n=10A353247
• a(n) = 1*binomial(n,2) + 3*binomial(n,3) + 6*binomial(n,4) + 10*binomial(n,5).at n=17A361474
• Numbers k such that A000005(k) = A000688(k).at n=17A369168
• Square array A(n,k) = A388979(A388981(n, k)), read by descending antidiagonals.at n=17A389169