222223

Appears in sequences

• Jacobsthal sequence (A001045) as represented in base 4.at n=13A081857
• Concatenation of n 2's followed by 3.at n=4A091628
• Expansion of g.f. (1-8*x)/((1-x)*(1-10*x)).at n=6A093135
• Near-repdigit semiprimes with 2 as repeated digit.at n=27A105983
• Numbers of the form 6*k+1 that use only digits 2 and 3.at n=10A152834
• Decimal representation of the reverted binary representation of n followed by digits substitution 0->2, 1->3.at n=32A176892
• Eight rooks and one berserker on a 3 X 3 chessboard. G.f.: (1 + 3*x)/(1 - 4*x - 3*x^2 + 6*x^3).at n=8A180147
• a(1) = 1; for n > 1: a(n) = smallest odd number greater than a(n-1) which does not use any digit used by a(n-1).at n=38A229364
• Pseudoprimes to base 5, written in base 5.at n=16A262102
• Array read by downward antidiagonals: T(k,n) is the least number that has k prime factors (counted with multiplicity) and is the concatenation of n primes, or -1 if there is no such number.at n=22A374376