27285

Appears in sequences

• 4-dimensional analog of centered polygonal numbers.at n=16A006323
• Numbers whose sum of divisors is a sixth power.at n=12A019424
• Number of (s,3) gates.at n=6A037295
• Numbers whose sum of divisors is 6^6 = 46656.at n=9A048256
• Building block is trapezoid formed from 3 equilateral triangles; sequence gives number of pieces (polytraps) that can be formed from n such trapezoids.at n=4A057782
• Odd composite numbers k such that cototient(k) - phi(k) = k - 2*phi(k) is an odd prime.at n=10A083255
• Numbers k such that the sum of the digits of sigma(k)^k is divisible by k.at n=16A109659
• G.f. satisfies: A(x) = 1/(1-x) * A(x^2)*A(x^3)*A(x^4)*...*A(x^n)*...at n=28A129374
• a(n) = n*Fibonacci(n) + binomial(n, 2).at n=16A132920
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 1", based on the 5-celled von Neumann neighborhood.at n=33A269908
• Number of permutations p of [n] such that max_{j=1..n} |p(j)-j| = 2.at n=11A323798
• Expansion of 1/(1 - 9*x/(1-x))^(5/3).at n=4A377235
• Array read by antidiagonals: T(n,k) is the number of nonequivalent series-parallel networks with longest path of at most n edges and largest cut set of at most k edges.at n=38A391484
• Array read by antidiagonals: T(n,k) is the number of nonequivalent series-parallel networks with longest path of at most n edges and largest cut set of at most k edges.at n=42A391484