cp's OEIS Frontend

A336779 a(n) is the largest power of n such that all numbers n^k <= a(n), k=1,..,A336778(n)-1 can be exactly represented as double precision 64-bit floating point numbers according to the IEEE 754 standard. If a(n) is a power of 2, it is replaced by the corresponding negated exponent of 2.

%I A336779 #11 Aug 10 2020 06:23:12
%S A336779 -1023,5559060566555523,-1022,2384185791015625,
%T A336779 47751966659678405306351616,1628413597910449,-1023,1853020188851841,
%U A336779 10000000000000000000000,4177248169415651,410186270246002225336426103593500672,3937376385699289,426878854210636742656,1946195068359375,-1020
%N A336779 a(n) is the largest power of n such that all numbers n^k <= a(n), k=1,..,A336778(n)-1 can be exactly represented as double precision 64-bit floating point numbers according to the IEEE 754 standard. If a(n) is a power of 2, it is replaced by the corresponding negated exponent of 2.
%C A336779 The "power of 2" escape clause serves to avoid the corresponding numbers with more than 305 decimal digits in the DATA field.
%H A336779 Hugo Pfoertner, <a href="/A336779/b336779.txt">Table of n, a(n) for n = 2..1600</a>
%F A336779 a(n) = n^(A336778(n)-1).
%e A336779 a(3) = 5559060566555523 = 3^33, because the next power 3^34 = 16677181699666569 cannot be exactly represented as a binary64 floating point number, but only rounded to 16677181699666568.
%Y A336779 Cf. A336774, A336775, A336776, A336778, A336780.
%K A336779 sign,fini,look
%O A336779 2,1
%A A336779 _Hugo Pfoertner_, Aug 04 2020