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A175949
Numbers obtained by concatenation of the binary representation of A175946(n) and A175945(n).
1
1, 2, 3, 6, 5, 4, 7, 14, 13, 10, 11, 12, 9, 8, 15, 30, 29, 26, 27, 18, 21, 20, 23, 28, 25, 22, 19, 24, 17, 16, 31, 62, 61, 58, 59, 50, 53, 52, 55, 34, 37, 42, 43, 36, 41, 40, 47, 60, 57, 54, 51, 38, 45, 44, 39, 56, 49, 46, 35, 48, 33, 32, 63, 126, 125, 122, 123, 114, 117, 116
OFFSET
1,2
COMMENTS
The operation as in A175948, but the run-length encoding of zeros (A175946) is placed left from the run-length encoding of ones (A175945).
EXAMPLE
n=9 is 1001 in binary. Run lengths of 0's are 2 (one run of length 2) and of 1's are 11 (two runs each of length 1). The concatenation of these lengths is 211, which is interpreted as 2 one's, 1 zero, 1 one, binary 1101, and recoded decimal as a(9)=8+4+1 =13.
MATHEMATICA
takelist[l_, t_] := Module[{lent, term}, Set[lent, Length[t]]; Table[l[[t[[y]]]], {y, 1, lent}]]
frombinrep[x_] := FromDigits[Flatten[Table[Table[If[OddQ[n], 1, 0], {d, 1, x[[n]]}], {n, 1, Length[x]}]], 2]
binrep[x_] := repcount[IntegerDigits[x, 2]]
onebinrep[x_]:=Module[{b}, b=binrep[x]; takelist[b, Range[1, Length[b], 2]]]
zerobinrep[x_]:=Module[{b}, b=binrep[x]; takelist[b, Range[2, Length[b], 2]]]
Table[frombinrep[Flatten[{zerobinrep[n], onebinrep[n]}]], {n, START, END}]
CROSSREFS
Sequence in context: A342102 A284460 A336963 * A166404 A337242 A371343
KEYWORD
base,nonn
AUTHOR
Dylan Hamilton, Oct 28 2010
STATUS
approved