1333333
domain: N
Appears in sequences
- Number of Fibonacci numbers F(k), k <= 10^n, which end in 9.at n=6A073556
- Expansion of g.f. (1+2*x)/((1-x)*(1-10*x)).at n=6A097166
- a(n) = Sum_{k=0..n} C(floor((n+1)/2),floor((k+1)/2)) * 3^k.at n=12A097169
- Numbers k such that the k-th triangular number contains only digits {1,8,9}.at n=17A119151
- a(n) = A133195(n)/3.at n=19A133201
- Minimum number k for which the digital sum of k*n is 4*n.at n=15A147824
- Minimum number k for which the digital sum of k*n is 10*n.at n=6A147830
- Mersenne primes written in base 4.at n=4A161677
- Fermat pseudoprimes to base 2 of the form (n^2 + 2*n)/3.at n=26A216170
- Fermat pseudoprimes to base 2 that are octagonal.at n=26A321868
- Starting from 1, successively take the smallest "Choix de Bruxelles" with factor 13 which is not already in the sequence.at n=6A360190