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A055018
Numbers n such that n and n+1 are modest (cf. A054986).
2
411, 811, 1421, 2036, 2044, 2054, 3054, 4036, 4044, 4054, 8036, 12036, 16036, 20036, 24036, 28036, 32036, 40011, 40044, 50054, 50074, 80011, 88296, 100110, 100270, 100369, 120296, 120404, 140021, 144242, 176296, 200044, 200270, 200369
OFFSET
1,1
LINKS
EXAMPLE
2036 is modest because Mod[2036, 36] = 20. 2037 is modest because Mod[2037, 037] = 2. Hence 2036 is this pair's modest twin representative.
PROG
(Haskell)
import Data.List (elemIndices)
a055018 n = a055018_list !! (n-1)
a055018_list = map (a054986 . (+ 1)) $ elemIndices 1 $
zipWith (-) (tail a054986_list) a054986_list
-- Reinhard Zumkeller, Mar 26 2012
CROSSREFS
Sequence in context: A212710 A187991 A090123 * A201844 A105211 A081378
KEYWORD
base,easy,nonn
AUTHOR
Hans Havermann, May 31 2000
STATUS
approved