70209

Appears in sequences

• a(n) = (10n+1)*(10n+9).at n=26A001535
• Numbers k such that 7*2^k - 1 is prime.at n=15A001771
• a(n+1) is the smallest number > a(n) such that the digits of a(n)^2 are all (with multiplicity) contained in the digits of a(n+1)^2, with a(0)=2.at n=25A067975
• Consider triangle in which n-th row contains the smallest set of n consecutive numbers whose LCM is divisible by primorial(n) (the product of first n primes). Sequence contains the first column.at n=24A083130
• Numbers k such that 2*10^k + 5*R_k - 4 is prime, where R_k = 11...1 is the repunit (A002275) of length k.at n=10A098930
• Compositions of n into parts 3, 5 and 7.at n=54A245367