TOPICS
Let 
be a function and let 
,
and define the cardinal series of 
with respect to the interval 
as the formal series
 |
where 
is the sinc function. If this series converges,
it is known as the cardinal function (or Whittaker cardinal function) of 
, denoted 
(McNamee et al. 1971).
." College Math. J. 21,
90-99, 1990.McNamee, J.; Stenger, F.; and Whitney, E. L. "Whittaker's
Cardinal Function in Retrospect." Math. Comput. 25, 141-154, 1971.Whittaker,
E. T. "On the Functions Which are Represented by the Expansions of the
Interpolation Theory." Proc. Roy. Soc. Edinburgh 35, 181-194,
1915.Whittaker, J. M. "On the Cardinal Function of Interpolation
Theory." Proc. Edinburgh Math. Soc. 1, 41-46, 1927.Whittaker,
J. M. Interpolary Function Theory. London: Cambridge University Press,
1935.Weisstein, Eric W. "Cardinal Function." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/CardinalFunction.html