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<DIV>Consider the constant (newly added to OEIS as
A100338):<BR> <BR>x=1.353871128429882374388894084016608124227333416812118556923672649787...<BR> </DIV>
<DIV>The continued fraction of this constant is A006519 (greatest power of 2
dividing n):</DIV>
<DIV>contfrac(x) = [1;2,1,4,1,2,1,8,1,2,1,4,1,2,1,16,...A006519(n),... ] </DIV>
<DIV> <BR>This constant x has the special property that the
<BR>continued fraction expansion of 2*x is equal to the <BR>continued
fraction expansion of x interleaved with 2's: <BR>contfrac(2*x) = [2;1, 2,2,
2,1, 2,4, 2,1, 2,2, 2,1, 2,8,... 2,A006519(n),...]. <BR> <BR>PARI code to
get 1000 digits:
<BR>\p1000<BR>CF=vector(1500,n,2^valuation(n,2));<BR>PQ=contfracpnqn(CF);<BR>x=PQ[1,1]/PQ[2,1]*1.0<BR> <BR>The
continued fraction of x^2 is interesting: contfrac(x^2) = </DIV>
<DIV>[1,1,4, 1,74, 1,8457, 1,186282390, 1,1,1,2,1,430917181166219,
11,37,1,4,2,</DIV>
<DIV>41151315877490090952542206046, 11,5,3,12,2,34,2,9,8,1,1,2,7,</DIV>
<DIV>13991468824374967392702752173757116934238293984253807017, ...]</DIV>
<DIV>and some of the partial quotients of x^2 seem
to grow exponentially. </DIV>
<DIV> </DIV>
<DIV>Has anyone seen this constant before? <BR>I wonder if it has some
nice series representations as well ... <BR> </DIV>
<DIV>Thanks,<BR> Paul</DIV></BODY></HTML>