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A094535
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a(n) is the smallest integer m such that A039995(m)=n.
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3
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1, 2, 13, 23, 113, 131, 137, 1013, 1031, 1273, 1237, 1379, 6173, 10139, 10193, 10379, 10397, 10937, 12397, 12379, 36137, 36173, 101397, 102371, 101937, 102973, 103917, 106937, 109371, 109739, 123797, 123917, 123719, 346137, 193719, 346173
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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COMMENTS
| A039995(a(n)) = n and A039995(m) < n for m < a(n). [Reinhard Zumkeller, Feb 01 2012]
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LINKS
| Reinhard Zumkeller, Table of n, a(n) for n = 0..100
C. Rivera, puzzle 265
Reinhard Zumkeller, Illustration of initial terms
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FORMULA
| << DiscreteMath`Combinatorica`; a1[n_]:=(r=IntegerDigits[n];b=Length[r]; c[k_]:=Union[KSubsets[r, k]];d[k_]:=Length[c[k]]; f[k_]:=Table[FromDigits[c[k][[j]]], {j, d[k]}]; (A={};Do[A=Join[A, f[k]], {k, b}]);A=Union[A]; Count[PrimeQ[A], True]);a[n_]:=(For[m=1, a1[m]!=n, m++ ]; m)
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EXAMPLE
| a(6)=137 because 137 is the smallest number m such that A039995(m)=6; the six number 3,7,13,17,37 & 137 are primes.
See also A205956 for a(100) = 39467139.
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PROG
| (Haskell)
import Data.List (elemIndex)
import Data.Maybe (fromJust)
a094535 n = a094535_list !! n
a094535_list = map ((+ 1) . fromJust . (`elemIndex` a039995_list)) [0..]
-- Reinhard Zumkeller, Feb 01 2012
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CROSSREFS
| Cf. A039995, A093301, A039997.
Cf. A205956.
Sequence in context: A165350 A195190 A090528 * A035244 A085822 A093301
Adjacent sequences: A094532 A094533 A094534 * A094536 A094537 A094538
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KEYWORD
| base,nonn,changed
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AUTHOR
| Farideh Firoozbakht (mymontain(AT)yahoo.com), May 08 2004
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