A Størmer number is a positive integer 
for which the greatest
prime factor 
of 
is at least 
. Every Gregory number 
can be expressed uniquely as a sum
of 
s where the 
s are Størmer numbers. The first few Størmer
numbers are given by Conway and Guy (1996) and Todd (1949) and are given by 
, 2, 4, 5, 6, 9, 10, 11, 12, 14, 15,
16, 19, 20, ... (OEIS A005528), corresponding
to greatest prime factors 2, 5, 17, 13, 37,
41, 101, 61, 29, ... (OEIS A005529).
Størmer Number
See also
Greatest Prime Factor, Gregory Number, Inverse TangentExplore with Wolfram|Alpha
References
Conway, J. H. and Guy, R. K. "Størmer's Numbers." The Book of Numbers. New York: Springer-Verlag, pp. 245-248, 1996.Sloane, N. J. A. Sequences A005528/M0950 and A005529/M1505 in "The On-Line Encyclopedia of Integer Sequences."Todd, J. "A Problem on Arc Tangent Relations." Amer. Math. Monthly 56, 517-528, 1949.Referenced on Wolfram|Alpha
Størmer NumberCite this as:
Weisstein, Eric W. "Størmer Number." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/StormerNumber.html