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A336780
a(n) is the least number of repetitions such that the result of the repeated execution of the multiplication f <- f*n started at f=1 produces an overflow, when the multiplication is performed using 64-bit double precision floats according to the IEEE 754 standard.
6
1024, 647, 512, 442, 397, 365, 342, 324, 309, 297, 286, 277, 269, 263, 256, 251, 246, 242, 237, 234, 230, 227, 224, 221, 218, 216, 214, 211, 209, 207, 205, 203, 202, 200, 199, 197, 196, 194, 193, 192, 190, 189, 188, 187, 186, 185, 184, 183, 182, 181, 180, 179, 178
OFFSET
2,1
COMMENTS
See A336774 for more information and links.
The overflow usually raises the corresponding exception, with +infinity returned as result.
LINKS
Hugo Pfoertner, Comparison with 128-bit results, range n=2..128, computed on x86-64 architecture.
KEYWORD
nonn,fini
AUTHOR
Hugo Pfoertner, Aug 07 2020
STATUS
approved