45123

Appears in sequences

• Concatenations of cyclic permutations of initial positive integers.at n=13A001292
• Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 27 ones.at n=24A031795
• Numbers with 5 distinct digits {1,2,3,4,5} such that all adjacent digits (as well as first and last digits) are coprime.at n=44A104972
• a(n) is the smallest number not already in the sequence, such that the concatenation of all a(n) displays the periodic digit string 1, 2, 3, 4, 5 (and repeat).at n=26A165303
• Fixed points of the function A260529(n) = concatenation of the positions of digits 9, 8,..., 0 in the decimal representation of n, using 1 for the rightmost digit etc., skipping digits which don't occur.at n=29A260275
• List of André permutations of the second kind.at n=21A278983
• Sum_{n>=0} a(n) * x^n / (n!)^2 = exp( (BesselI(0,2*sqrt(x)) - BesselJ(0,2*sqrt(x))) / 2 ).at n=7A346220