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<DIV>This sequence is twice A023758. Take a look at the formulas there.</DIV>
<DIV> </DIV>
<DIV>If you want to generate them in order, take differences of powers of 2, with the lower powers in reverse order:</DIV>
<DIV> </DIV>
<DIV>2^2-2^1, 2^3-2^1, 2^3-2^2, ...</DIV>
<DIV> </DIV>
<DIV>Franklin T. Adams-Watters<BR> </DIV> <BR>-----Original Message-----<BR>From: Alonso Del Arte <A href="mailto:alonso.delarte@gmail.com">alonso.delarte@gmail.com</A><BR><BR>
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<DIV class=AOLPlainTextBody id=AOLMsgPart_0_6bb8804b-411c-4e69-a56d-eb2fa17236e8><PRE><TT>I've just sent through the form a Mathematica command to calculate the
terms of A043569. It involves multiplying Mersenne numbers by powers
of 2 and sorting. It works but it's not terribly elegant.
Is there a recurrence relation for this sequence? I've tried several
different things along the lines of
a(1) = 2, a(n) = a(n -1) + log_2 a(n - 1) + log_2 a(n - 2) etc., etc.,
and they work except after a(n - 1) becomes a power of two, or before.
Any suggestions?
Al
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