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A122416 Numbers from an irrationality measure for e, with a(1) = 2. 4
2, 3, 4, 5, 6, 4, 8, 5, 7, 6, 12, 5, 14, 8, 6, 7, 18, 7, 20, 6, 8, 12, 24, 5, 11, 14, 10, 8, 30, 6, 32, 9, 12, 18, 8, 7, 38, 20, 14, 6, 42, 8, 44, 12, 7, 24, 48, 7, 15, 11, 18, 14, 54, 10, 12, 8, 20, 30, 60, 6, 62, 32, 8, 9, 14, 12, 68, 18, 24, 8, 72, 7, 74, 38, 11, 20, 12, 14, 80, 7, 10 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

If n > 1, then a(n)! is the smallest factorial such that |e - m/n| > 1/a(n)! for any integer m.

a(n)! is the second smallest factorial divisible by n.

REFERENCES

Mohammad K. Azarian, Euler's Number Via Difference Equations, International Journal of Contemporary Mathematical Sciences, Vol. 7, 2012, No. 22, pp. 1095 - 1102.

J. Sondow, A geometric proof that e is irrational and a new measure of its irrationality, Amer. Math. Monthly 113 (2006) 637-641.

LINKS

Table of n, a(n) for n=1..81.

Index entries for sequences related to factorial numbers.

J. Sondow, A geometric proof that e is irrational and a new measure of its irrationality

FORMULA

a(n) = A002034(n) + 1.

EXAMPLE

a(6) = S(6) + 1 = 3 + 1 = 4.

CROSSREFS

Cf. A001113, A002034, A092495, A122417.

Sequence in context: A097751 A070667 A245349 * A134665 A271832 A063260

Adjacent sequences:  A122413 A122414 A122415 * A122417 A122418 A122419

KEYWORD

nonn

AUTHOR

Jonathan Sondow, Sep 03 2006

STATUS

approved

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Last modified February 18 05:48 EST 2018. Contains 299298 sequences. (Running on oeis4.)