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A090424
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Smallest number that can be written in binary representation as concatenation of other primes in exactly n ways.
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2
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2, 11, 23, 47, 175, 95, 189, 375, 191, 381, 763, 1015, 751, 383, 765, 1023, 1407, 2045, 767, 8123, 1919, 5999, 1533, 5623, 4063, 3067, 3007, 3039, 1535, 6013, 6077, 8183, 7935, 11247, 3069, 12023, 12143, 6139, 6015, 6111, 6127, 3071, 6079, 6135, 7679, 32507
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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n=6: a(6)=95 -> '1011111': '10"11111'==2"31, '10"11"111'==2"3"7, '10"111"11'==2"7"3, '101"11"11'==5"3"3, '1011"111'==11"7 and '10111"11'==23"3, therefore A090418(95)=6.
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PROG
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(Haskell)
import Data.List (elemIndex)
import Data.Maybe (fromJust)
a090424 = (+ 1) . fromJust . (`elemIndex` a090418_list)
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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