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A287434
Largest denominator used in the Egyptian fraction representation of 1-1/(2n+1) by the odd greedy expansion algorithm, without repeats.
2
45, 24885, 315, 45, 340725, 196365, 15, 10965, 196365, 10465, 1652115781968795, 340725, 25245, 3976914451825623169001741646052688658398236092769201887156089117865, 15345, 13695, 6232413355673505, 79365
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OFFSET
1,1
COMMENTS
The odd version of
A100695
.
LINKS
Amiram Eldar,
Table of n, a(n) for n = 1..269
Kevin Brown,
Odd-Greedy Unit Fraction Expansions
.
Wikipedia,
Odd greedy expansion
.
EXAMPLE
For n = 2, 1-1/(2n+1) = 4/5 = 1/3 + 1/5 + 1/7 + 1/9 + 1/79 + 1/24885, thus a(2) = 24885.
MATHEMATICA
odd[n_]:=If[OddQ[n], n, n+1]; a={}; For[n=0, n<100, n++; dlast=0; k=2n/(2n+1); s1=0; While[k>0, s2=odd[Ceiling[1/k]]; If[s2==s1, s2+=2]; dlast=s2; k=k-1/s2; s1=s2]; a=AppendTo[a, dlast]]; a
CROSSREFS
Cf.
A100695
,
A286720
.
Sequence in context:
A171118
A199521
A007537
*
A225991
A125113
A354362
Adjacent sequences:
A287431
A287432
A287433
*
A287435
A287436
A287437
KEYWORD
nonn
AUTHOR
Amiram Eldar
, May 30 2017
STATUS
approved