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A020473 Egyptian fractions: number of partitions of 1 into reciprocals of positive integers <= n. 15
1, 2, 3, 5, 6, 13, 14, 24, 34, 60, 61, 168, 169, 252, 627, 1011, 1012, 2430, 2431, 7212, 15024, 16553, 16554, 50219, 60008, 64284, 92071, 260178, 260179, 844846, 844847, 1431187, 2608883, 2661217, 7946814, 22692855, 22692856, 22911815 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Number of ways to represent 1 = Sum_{k=1..n} b(k)/k, where the b(k) >= 0. - Franklin T. Adams-Watters, Aug 01 2006
LINKS
FORMULA
a(n) = Sum(A092666(i), i=1..n).
For prime p, a(p) = a(p-1) + 1. - Max Alekseyev, May 07 2012
MATHEMATICA
Timing[Table[Length[IntegerPartitions[1, All, 1/Range[n]]], {n, 1, 20}]] (* Ben Branman, Apr 21 2012 *)
CROSSREFS
Sequence in context: A253644 A100330 A331043 * A098833 A075371 A218948
KEYWORD
nonn
AUTHOR
STATUS
approved

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Last modified March 28 20:05 EDT 2024. Contains 371254 sequences. (Running on oeis4.)