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A105053
Least number k such that (1+1/k)^k yields n digits of e (A001113).
0
1, 74, 164, 4822, 16609, 743325, 1640565, 45332594
OFFSET
1,2
EXAMPLE
a(1) = 1 because (1+1/1)^1= 2 which equals e in the units place.
a(2) = 74 because (1+1/73)^73 = 2.69989... but (1+1/74)^74 = 2.700139...; thus 74 is the least number which will give e to 2 place accuracy, namely 2.7.
MATHEMATICA
f[0] = 0; f[n_] := f[n] = Block[{k = f[n - 1] + 1, d = FromDigits[{Take[ RealDigits[E, 10, 111][[1]], n], 1}]}, While[(1 + 1/k)^k < d, k++ ]; k]; Table[ f[n], {n, 6}]
CROSSREFS
Cf. A001113.
Sequence in context: A044325 A044706 A217991 * A260171 A044406 A044787
KEYWORD
nonn,base
AUTHOR
Robert G. Wilson v, Apr 02 2005
STATUS
approved