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A083347 Numbers n such that r(n) = Sum(e/p: n=Prod(p^e)) < 1. 5
1, 2, 3, 5, 6, 7, 9, 10, 11, 13, 14, 15, 17, 19, 21, 22, 23, 25, 26, 29, 31, 33, 34, 35, 37, 38, 39, 41, 42, 43, 45, 46, 47, 49, 50, 51, 53, 55, 57, 58, 59, 61, 62, 63, 65, 66, 67, 69, 70, 71, 73, 74, 75, 77, 78, 79, 82, 83, 85, 86, 87, 89, 91, 93, 94, 95, 97, 98, 99, 101, 102 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

A083345(a(n) < A083346(a(n)); A083345(A051674(n))=A083346(A051674(n)), A083345(A083348(n))>A083346(A083348(n)).

Numbers n whose arithmetic derivative (A003415) n' < n. - T. D. Noe, Apr 24 2011

LINKS

T. D. Noe, Table of n, a(n) for n = 1..1000

PROG

(Haskell)

import Data.List (findIndices)

a083347 n = a083347_list !! (n-1)

a083347_list = findIndices (< 0) $ zipWith (-) a003415_list [0..]

-- Reinhard Zumkeller, May 10 2011

CROSSREFS

Cf. A003415, A072873, A051674, A083348.

Sequence in context: A193303 A092418 A004195 * A137217 A023705 A188070

Adjacent sequences:  A083344 A083345 A083346 * A083348 A083349 A083350

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Apr 25 2003

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Last modified February 17 03:18 EST 2012. Contains 205978 sequences.