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A219092 Floor(e^(n + 1/2)). 1
1, 4, 12, 33, 90, 244, 665, 1808, 4914, 13359, 36315, 98715, 268337, 729416, 1982759, 5389698, 14650719, 39824784, 108254987, 294267566, 799902177, 2174359553, 5910522063, 16066464720, 43673179097, 118716009132, 322703570371 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

a(n) is the number k such that {log(k} < 1/2 < {log(k+1)}, where { } = fractional part.  Equivalently, the jump sequence of f(x) = log(x), in the sense that these are the positive integers k for which round(log(k)) < round(log(k+1)).  For a guide to related sequences, see A219085.

LINKS

Table of n, a(n) for n=0..26.

FORMULA

a(n) = [e^(n + 1/2)].

EXAMPLE

log(1) = 0.000... ; log(2) = 0.693...

log(4) = 1.386... ; log(5) = 1.609...

log(12) = 2.484... ; log(13) = 2.564...

MATHEMATICA

Table[Floor[E^(n + 1/2)], {n, 0, 100}]

CROSSREFS

Cf. A219085.

Sequence in context: A186025 A027941 A293064 * A135254 A326804 A000754

Adjacent sequences:  A219089 A219090 A219091 * A219093 A219094 A219095

KEYWORD

nonn,easy

AUTHOR

Clark Kimberling, Jan 01 2013

STATUS

approved

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Last modified August 11 15:12 EDT 2020. Contains 336428 sequences. (Running on oeis4.)