5000000000
domain: N
Appears in sequences
- Expansion of g.f. (1+2*x+5*x^2)/(1-10*x^3).at n=29A051109
- a(n) = floor(n^n/2).at n=10A057065
- a(n) = floor(10^10/n).at n=1A057072
- a(n) = denominator(N), where N = 0.246...(2n) is the concatenation of the first n even numbers after decimal point.at n=6A078260
- Expansion of (1-5*x)/(1-10*x).at n=10A093143
- a(n)=Product{k=0..n, 1+4^A010060(k)}/2.at n=19A101654
- Numbers with no "e" in Dutch.at n=7A114644
- Numbers with no "e" in Dutch (Miljard without "een").at n=8A115072
- Assign weights to the nonnegative integers as in A073327, then sort them by weight.at n=35A152611
- a(n) = ceiling(n^n/2).at n=10A168658
- Period of powers of 3 mod 10^n.at n=10A216099
- Period of powers of 11 mod 10^n.at n=9A216156
- Period of powers of 7 mod 10^n.at n=11A216164
- Let x(1)x(2)... x(2q) denote the decimal expansion of a number n with an even number of digits. The sequence lists the numbers n such that (10^q-a)*(10^q-b) = n where a is the number having the digits x(1)x(2)...x(q) and b is the number having the digits x(q+1)x(q+2)...x(2q).at n=22A245587
- The decimal representation of the average of the digits of n starts with the digits of n.at n=23A257829
- a(n) = 2^((n-1) mod 2)*5*10^floor((n-1)/2).at n=19A268100