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A120355 a(n) = min{k>0: the n-th convergent to e equals m/k! for some m}. 0
1, 1, 3, 4, 7, 8, 13, 31, 67, 13, 89, 83, 18089, 5441, 17377, 36269, 26021, 4909, 10391023, 1097, 28879, 1846921, 519691, 1329313, 793279, 7553783, 3308341, 65676881, 662407, 677311, 2425388512913, 4403182913, 10832561 (list; graph; refs; listen; history; internal format)
OFFSET

0,3

COMMENTS

Smarandache numbers of denominators of convergents to e.

REFERENCES

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

LINKS

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

FORMULA

a(n) = A002034(A007677(n)).

EXAMPLE

The 6th convergent to e is 87/32 and 32 divides 8! but not 7!, so a(6) = 8.

CROSSREFS

Cf. A002034, A007677.

Sequence in context: A008368 A023054 A060023 * A114210 A073271 A117471

Adjacent sequences:  A120352 A120353 A120354 * A120356 A120357 A120358

KEYWORD

hard,more,nonn

AUTHOR

Jonathan Sondow (jsondow(AT)alumni.princeton.edu), Aug 16 2006

EXTENSIONS

Extended by Max Alekseyev (maxale(AT)gmail.com), Jul 28 2009

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Last modified February 17 10:05 EST 2012. Contains 206009 sequences.