18372

Appears in sequences

• Number of 1's in n-th term of A007651.at n=37A022466
• 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 90.at n=32A031588
• Numbers k such that phi(phi(k)) = sum of prime factors of k.at n=13A075863
• Number of 3-dimensional lattice paths running from (0,0,0) to (n,n,n), lying in {(x,y,z) : 0<=x<=y<=z} and using the steps (1,0,0), (0,1,0), (0,0,1), (1,1,0), (1,0,1), (0,1,1), (1,1,1).at n=4A088594
• Number of partitions that are "3-close" to being self-conjugate.at n=45A108962
• Numbers k such that (k!-7)/7 is prime.at n=17A139202
• Number of 3 X 3 magilatin squares with positive values and magic sum n.at n=19A173549
• Numbers k such that phi(k-6) = phi(k) = phi(k+6).at n=25A217006
• Number of partitions of n in which any two parts differ by at most 6.at n=49A218508
• Decimal representation of the x-axis, from the left edge to the origin, of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 629", based on the 5-celled von Neumann neighborhood.at n=14A283389
• a(n) = Sum_{k=1..n} binomial(n,k) * tau(k) * tau(n - k + 1), where tau = A000005.at n=10A328681
• Expansion of Product_{k>=1} (1 + x^k)^(3^(k-1)).at n=9A343360
• Triangle T(n,k) read by rows: T(n,k) is the coefficient of x^k of the monic polynomial (1+x)^n + ((2*(1+x))^n - (2+x)^n) / x.at n=51A391610