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A136375
Irregular array read by rows, where n-th row gives denominators of the Egyptian fraction expansion, derived using the greedy algorithm, for the absolute value of the fractional part of the (2n)th Bernoulli number.
1
0, 6, 30, 42, 30, 14, 231, 4, 322, 125580, 6, 11, 802, 1124805, 2, 3, 8, 78, 41496, 9, 77, 6930, 9, 83, 34362, 4, 322, 125580, 6, 15, 870, 2, 3, 15, 1557, 9291398, 172660144297410, 11, 802, 1124805, 6, 4, 13, 171, 885780, 6
OFFSET
0,2
EXAMPLE
Triangle begins:
0,
6,
30,
42,
30,
14, 231
4, 322, 125580
...
The 10th Bernoulli number is 5/66. The largest unit fraction <= 5/66 is 1/14. Now 5/66 - 1/14 is 1/231, which is itself a unit fraction. So the Egyptian fraction representation of 5/66 is 1/14 + 1/231. Therefore row 5 of this array is (14,231).
CROSSREFS
Row sums: A151711. - N. J. A. Sloane, Jun 07 2009
Sequence in context: A062268 A067879 A334900 * A138706 A027762 A002445
KEYWORD
more,nonn,tabf
AUTHOR
Leroy Quet, Mar 29 2008
EXTENSIONS
Row 6 from N. J. A. Sloane, Jun 07 2009
Better definition and more terms from T. D. Noe, Jun 07 2009
STATUS
approved