21472

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 73.at n=30A031571
• Bessel function J_0(n) is a monotonically decreasing positive sequence.at n=39A046960
• Sums of squared terms in rows of triangle A112555.at n=10A112556
• Unsigned row sums of triangle A114700.at n=20A116466
• Sequence of which A078783 is the Recamán transform.at n=42A117073
• Number at end of segment n of A117073.at n=13A117075
• Phi(n) values in A115921.at n=28A216381
• Number of (n+2)X(5+2) 0..3 arrays with no element unequal to a strict majority of its horizontal, vertical, diagonal and antidiagonal neighbors, with values 0..3 introduced in row major order.at n=5A231438
• Number of (n+2)X(6+2) 0..3 arrays with no element unequal to a strict majority of its horizontal, vertical, diagonal and antidiagonal neighbors, with values 0..3 introduced in row major order.at n=4A231439
• T(n,k)=Number of (n+2)X(k+2) 0..3 arrays with no element unequal to a strict majority of its horizontal, vertical, diagonal and antidiagonal neighbors, with values 0..3 introduced in row major order.at n=49A231441
• T(n,k)=Number of (n+2)X(k+2) 0..3 arrays with no element unequal to a strict majority of its horizontal, vertical, diagonal and antidiagonal neighbors, with values 0..3 introduced in row major order.at n=50A231441
• Row sums of the triangular array A246696.at n=34A246697
• Numbers that are nontrivially palindromic in three or more consecutive integer bases.at n=15A279093
• Number of rooted unlabeled bipartite cubic maps on a compact closed oriented surface with 2*n vertices (and thus 3*n edges), with a(0) = 1.at n=5A292187
• Expansion of 1/(1 + x/(1 + x/(1 + x^2/(1 + x/(1 + x^3/(1 + x/(1 + x^4/(1 + ...)))))))), a continued fraction.at n=19A296202
• Expansion of e.g.f. Product_{k>=1} ((1 + x^k)/(1 - x^k))^(tau(k)/k), where tau is A000005.at n=6A318977
• Numbers k such that 405*2^k+1 is prime.at n=28A323102
• G.f. A(x,y) satisfies 1/x = Sum_{n=-oo..+oo} A(x,y)^n * (A(x,y)^n + y)^(n+1), as a triangle of coefficients T(n,k) of x^n*y^k in A(x,y), read by rows.at n=39A379200