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A190784
Numbers whose binary representation is a substring of the concatenation of the binary representation of all smaller nonnegative integers not listed earlier, taken in decreasing order.
1
2, 6, 7, 9, 11, 12, 14, 17, 19, 20, 21, 22, 25, 26, 27, 28, 29, 30, 31, 33, 34, 37, 39, 40, 41, 42, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 56, 57, 58, 59, 60, 61, 62, 63, 65, 67, 69, 71, 72, 73, 74, 77, 78, 80, 81, 82, 84, 86, 87, 89, 90, 92, 93, 94
OFFSET
1,1
COMMENTS
Also, nonnegative integers which do not occur in A118250.
Up to the reversed (decreasing) order of concatenation, a binary analog of Hannah Rollman's numbers A048992.
EXAMPLE
The binary representation of 2="10"[2] is a substring of the concatenation of 1 and 0, therefore a(1)=2. This term a(1)=2="10" will henceforth be excluded from the concatenations considered in the sequel.
The binary representations of 3, 4 and 5 are not a substrings of concat("1", "0") resp. concat("11", "1", "0") resp. concat("100", "11", "1", "0"). (Note that 2="10" is not among the concatenated numbers.)
But 6="110"[2] is again a substring of concat(5="101", 4="100", 3="11", "1", "0"), therefore a(2)=6. In the sequel, a(2)=6="110" will now also be always excluded from the concatenations, as is a(1)=2.
CROSSREFS
Analog of A128291 for the "with reversal" variant A118250 of A118248.
Sequence in context: A206446 A079335 A278999 * A344167 A061416 A190247
KEYWORD
nonn,base
AUTHOR
M. F. Hasler, Dec 29 2012
STATUS
approved