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Table of n, a(n) for n=1..18.
a(n)=a(n-1)+10^(n-1)*(2-[a(n-1)/2^(n-1) mod 2]) i.e. a(n) ends with a(n-1); if (n-1)-th term is divisible by 2^n then n-th term begins with a 2, if not then n-th term begins with a 1.
Cf. A023396, A050621, A050622, A035014.
Sequence in context: A185190 A227460 A091481 * A091854 A141141 A128571
Adjacent sequences: A053309 A053310 A053311 * A053313 A053314 A053315
Henry Bottomley, Mar 06 2000