616666

Appears in sequences

• a(n) = Sum_{k=0..10} binomial(n,k).at n=20A008863
• a(n) = 2^(n-1) + ((1 + (-1)^n)/4)*binomial(n, n/2).at n=20A027306
• a(n) = Sum_{i=0..n} binomial(2*n, i).at n=10A032443
• a(n) = 2^n - C(n,0)- ... - C(n,9).at n=20A035042
• Smallest semiprime containing exactly n 6's.at n=4A104729
• Near-repdigit semiprimes with 6 as repeated digit.at n=28A105987
• Expansion of ((1 + x - 2x^2) + (1+x)*sqrt(1-4x^2))/(2(1-4x^2)).at n=21A116406
• T(n,k)=Number of binary arrays of length n+2*k-1 with no more than k ones in any length 2k subsequence (=50% duty cycle).at n=45A212402
• A(n,k) = Sum_{j=0..floor(n/k)} binomial(2*n,k*j+n), square array A(n,k) read by antidiagonals, for n >= 0, k >= 1.at n=65A307665