20937

Appears in sequences

• Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 96.at n=34A031594
• Numbers k such that k and 5*k, taken together, are pandigital.at n=14A115925
• a(n) = 58*n^2 - 1.at n=18A158668
• Number of (w,x,y,z) with all terms in {1,...,n} and 2w=x+y+z.at n=37A212068
• Number of triples (w,x,y) with all terms in {0,...,n} and |w-x| + |x-y| <= w+x+y.at n=27A213481
• G.f.: Product_{k>=1} 1/(1-x^k)^(2*k-1).at n=14A253289
• Number of n X n 0..1 arrays with every element equal to 0, 2, 3, 4 or 5 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.at n=4A302883
• Number of nX5 0..1 arrays with every element equal to 0, 2, 3, 4 or 5 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.at n=4A302886
• T(n,k)=Number of nXk 0..1 arrays with every element equal to 0, 2, 3, 4 or 5 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.at n=40A302889
• Number of 5Xn 0..1 arrays with every element equal to 0, 2, 3, 4 or 5 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.at n=4A302892