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I'm looking for a way to mathematically combine two concepts: LFSRs, and Barrel Shifters

I'm looking for a way, in O(1) time, to shift an LFSR loop a given number of shifts.

What I'm hoping to find is a simple process where I have the current state of the LFSR and the number of times I want to shift from that state as parameters to a quick/easy process.

At first I just thought about looking at all the taps, then moving the taps over by 1 and looking at them again, finding the shift in bit each time and appending it onto the end but of course this isn't O(1) and it gets complicated if I want to shift so many times that a tap would "slide off" the original LFSR state.

I may be in the wrong place to ask this because I'm looking for a way to do this programmatically. Although any incite into how it's possible (or why it's impossible) would be very helpful.

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    I'm not sure such a way exists...2011-02-17
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    me either, but I can hope2011-02-17
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    @Dilip: Please see the discussion [on this meta answer and comments](http://meta.math.stackexchange.com/a/4000/622).2012-04-18
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    @AsafKaragila I deleted the lfsr tag, and so it can stay on the list of deleted tags on meta2012-04-18

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