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A092666 a(n) = number of Egyptian fractions 1 = 1/x_1 + ... + 1/x_k (for any k), with 0 < x_1 <= ... <= x_k = n. 5
1, 1, 1, 2, 1, 7, 1, 10, 10, 26, 1, 107, 1, 83, 375, 384, 1, 1418, 1, 4781, 7812, 1529, 1, 33665, 9789, 4276, 27787, 168107, 1, 584667, 1, 586340, 1177696, 52334, 5285597, 14746041, 1, 218959, 13092673, 84854683, 1, 279357910, 1, 491060793, 2001103921 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

LINKS

Toshitaka Suzuki, Table of n, a(n) for n = 1..390

Index entries for sequences related to Egyptian fractions

FORMULA

a(n) = A020473(n) - A020473(n-1).

a(n) = 1 if n is prime.

EXAMPLE

a(4) = 2 since there are two fractions 1=1/2+1/4+1/4 and 1=1/4+1/4+1/4+1/4.

CROSSREFS

Cf. A020473, A092667, A092669, A002966, A000058, A259633.

Sequence in context: A160417 A117044 A280691 * A019426 A128747 A205945

Adjacent sequences:  A092663 A092664 A092665 * A092667 A092668 A092669

KEYWORD

nonn

AUTHOR

Max Alekseyev, Mar 02 2004

EXTENSIONS

Edited by Max Alekseyev, May 05 2010

STATUS

approved

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Last modified November 21 01:23 EST 2019. Contains 329348 sequences. (Running on oeis4.)