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A238593
Smallest m such that the n-th prime occurs as substring in A019518(n).
1
1, 2, 3, 4, 5, 6, 7, 8, 2, 10, 7, 12, 13, 14, 15, 16, 17, 18, 19, 5, 21, 22, 23, 24, 25, 26, 27, 28, 29, 6, 31, 7, 12, 34, 35, 36, 37, 38, 19, 21, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 32, 59, 60, 61, 11, 63, 33, 12, 7, 66, 68
OFFSET
1,2
COMMENTS
a(n) <= n; see A165450 for earley bird primes: A165450(n) = A000040(m) with a(m) < m.
LINKS
EXAMPLE
n=10, prime(10)=29 occurs first in A019518(10)=2357111317192329, therefore a(10) = 10;
prime(11)=31 occurs already in A019518(7)=2357111317, therefore a(11) = 7.
PROG
(Haskell)
import Data.List (isInfixOf, findIndex); import Data.Maybe (fromJust)
a238593 n = (+ 1) $ fromJust $ findIndex
(isInfixOf $ show $ a000040 n) (scanl1 (++) $ map show a000040_list)
CROSSREFS
Sequence in context: A245345 A043268 A346973 * A279649 A278060 A160597
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Mar 03 2014
STATUS
approved