A287434 Largest denominator used in the Egyptian fraction representation of 1-1/(2n+1) by the odd greedy expansion algorithm, without repeats.

45, 24885, 315, 45, 340725, 196365, 15, 10965, 196365, 10465, 1652115781968795, 340725, 25245, 3976914451825623169001741646052688658398236092769201887156089117865, 15345, 13695, 6232413355673505, 79365

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