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A Digit-by-Digit Algorithm for mth Root Extraction
December 2007 (vol. 56 no. 12)
pp. 1696-1706
A general digit-recurrence algorithm for the computation of the m-th root (with m integer) is presented in this paper. Based on the concept of completing the m-th root, a detailed analysis of the convergence conditions is performed and iteration-independent digit-selection rules are obtained for any radix and redundant digit set. A radix- 2 version for m-th rooting is also studied, together with closed formulas for both the digit selection rules and the number of bits required to perform correct selections.

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Index Terms:
integer rooting, digit-by-digit algorithms, higher radix, computer arithmetic
Citation:
Paolo Montuschi, Javier D. Bruguera, Luigi Ciminiera, José-Alejandro Piñeiro, "A Digit-by-Digit Algorithm for mth Root Extraction," IEEE Transactions on Computers, vol. 56, no. 12, pp. 1696-1706, Dec. 2007, doi:10.1109/TC.2007.70764
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