A240132 Number of solutions of 1/x_1 + 1/x_2 + ... + 1/x_{2n-1} = 1 in distinct odd numbers > 1.

0, 0, 0, 0, 5, 379118

Offset

1,5

Comments

The next term is a(7) > 467871307.

Links

Table of n, a(n) for n=1..6.

R. Arce-Nazario, F. Castro, and R. Figueroa, On the number of solutions of Sum_{i = 1..11} 1/x_i = 1 in distinct odd natural numbers, J. Number Theory, 133 (2013), 2036-2046.

C. Elsholtz, Review of ``On the number of solutions of sum_{i = 1..11} 1/x_i = 1 in distinct odd natural numbers'' by R. Arce-Nazario, F. Castro, and R. Figueroa, zbMATH 1270.11033.

Example

If 1 < x_1 < x_2 < x_3 are odd, then 1/x_1 + 1/x_2 + 1/x_3 < 3/3 = 1, so a(2) = 0.

Crossrefs

The five sets of 9 odd numbers are: A201644, A201646, A201647, A201648, A201649.

See A238795 and A239036 for specific sets of 11 odd numbers.

Sequence in context: A123751 A152516 A295532 * A067509 A067502 A318752

Adjacent sequences: A240129 A240130 A240131 * A240133 A240134 A240135

Keyword

hard,more,nonn

Author

Jonathan Sondow, Apr 21 2014

Status

approved