22457

Appears in sequences

• Numbers k such that k, k+2, k+4, k+6, k+8, k+10 are semiprimes.at n=16A092128
• G.f.: A(x) = x/(1-x) o x/(1-x^2) o x/(1-x^4) o x/(1-x^8) o..., composition of functions x/(1 - x^{2^n}) for n=0,1,2,3,...at n=18A136752
• Positive numbers y such that y^2 is of the form x^2+(x+617)^2 with integer x.at n=8A160176
• Number of (w,x,y,z) with all terms in {1,...,n} and w+x=|x-y|+|y-z|.at n=35A212676
• Number of permutations of length n avoiding 12345 and containing exactly 1 occurrence of 12354.at n=8A224296
• a(n) = Sum_{k=2..n-1} k*A259698(n,k).at n=9A259700
• a(n) = Sum_{k=0..n} (k*n+1)^(n-k) * binomial(n,k).at n=5A356811
• Expansion of e.g.f. sinh(2 * (exp(x)-1)) / 2.at n=8A357598
• The lowest positive-integer center for a square spiral whose center lies in an n X n square of nonprimes.at n=8A358720
• Expansion of e.g.f. exp(2*x) / (1 - x*exp(3*x)).at n=5A368293