Approximate formulae for certain prolate spheroidal wave functions valid for large values of both order and band-limit
نویسندگان
چکیده
We construct asymptotic formulae for the approximation of certain prolate spheroidal wave functions and of the corresponding eigenvalues. We investigate two regimes: when the ratio c/m decays, and when both c and m grow, but the ratio c/m stays bounded. Both the regions of validity and the accuracies of the obtained expansions are illustrated with numerical examples. © 2006 Elsevier Inc. All rights reserved.
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