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A143261 Sequence of sum of Gray code Binary digits for Pascal's triangle sequence : t(n,m)=GrayCodeBinarySum[Binomial[n,m]). 0
1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 1, 3, 5, 3, 1, 1, 7, 15, 15, 7, 1, 1, 5, 1, 15, 1, 5, 1, 1, 1, 31, 19, 19, 31, 1, 1, 1, 3, 9, 9, 83, 9, 9, 3, 1, 1, 11, 27, 63, 65, 65, 63, 27, 11, 1, 1, 15, 55, 17, 221, 65, 221, 17, 55, 15, 1, 1, 7, 13, 239, 495, 297, 297, 495, 239, 13, 7, 1 (list; graph; refs; listen; history; internal format)
OFFSET

1,5

COMMENTS

This sequence does not match its definition. - Franklin T. Adams-Watters, Sep 29 2011.

The result here is different than the Gray Code base ten result:

all the elements are odd: modulo two they would be ones.

Row sums are:

{1, 2, 5, 4, 13, 46, 29, 104, 127, 334, 683, 2104}.

REFERENCES

Weisstein, Eric W. "Gray Code." http : // mathworld.wolfram.com/GrayCode.html

FORMULA

t(n,m)=GrayCodeBinarySum[Binomial[n,m]).

EXAMPLE

{1},

{1, 1},

{1, 3, 1},

{1, 1, 1, 1},

{1, 3, 5, 3, 1},

{1, 7, 15, 15, 7, 1},

{1, 5, 1, 15, 1, 5, 1},

{1, 1, 31, 19, 19, 31, 1, 1},

{1, 3, 9, 9, 83, 9, 9, 3, 1},

{1, 11, 27, 63, 65, 65, 63, 27, 11, 1},

{1, 15, 55, 17, 221, 65, 221, 17, 55, 15, 1},

{1, 7, 13, 239, 495, 297, 297, 495, 239, 13, 7, 1}

MATHEMATICA

GrayCodeList[k_] := Module[{b = IntegerDigits[k, 2], i}, Do[ If[b[[i - 1]] == 1, b[[i]] = 1 - b[[i]]], {i, Length[b], 2, -1} ]; b ]; b = Table[Table[Sum[GrayCodeList[Binomial[n, k]][[m + 1]]*2^m, {m, 0, Length[GrayCodeList[Binomial[n, k]]] - 1}], {k, 0, n}], {n, 0, Length[a]}]; Flatten[b]

CROSSREFS

Cf. A098957.

Sequence in context: A001165 A137420 A134866 * A204116 A093421 A146531

Adjacent sequences:  A143258 A143259 A143260 * A143262 A143263 A143264

KEYWORD

nonn,uned,obsc,base

AUTHOR

Roger L. Bagula and Gary W. Adamson (rlbagulatftn(AT)yahoo.com), Oct 21 2008

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Last modified February 15 05:45 EST 2012. Contains 205694 sequences.