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A175335
a(1)=1. For n>1, a(n) equals the smallest number > a(n-1) of the form a(k) U j U a(k) U j, where U represents concatenation (written in decimal) of the binary representation of the arguments, where 1 <= k < n, and j = {0} or {1}.
1
1, 10, 15, 660, 693, 990, 1023, 2704680, 2706729, 2839914, 2841963, 4057020, 4059069, 4192254, 4194303, 45377005980240, 45377014368849, 45411382499922, 45411390888531, 47645856279252, 47645864667861, 47680232798934, 47680241187543
OFFSET
1,2
COMMENTS
Each term of this sequence exists in sequence A175336.
EXAMPLE
10 (decimal), a term of the sequence, written in binary is 1010. Letting j={0}, we have that the decimal value of 1010 U 0 U 1010 U 0 = 1010010100, which is 660, is in the sequence.
CROSSREFS
Sequence in context: A114703 A134515 A232608 * A167788 A341012 A072968
KEYWORD
base,nonn
AUTHOR
Leroy Quet, Apr 14 2010
EXTENSIONS
More terms from Max Alekseyev, Jun 13 2011
STATUS
approved