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 A054258 Concatenation of n in base 2 up to base 10 and n in base 10 down to base 2 is prime, all numbers are interpreted as decimals. 2
 2607, 4007, 4069, 7597, 12411, 13583, 23041, 31113, 32619, 46187, 48469, 55777, 61411, 64387, 71143, 73837, 84761, 103559, 123797, 124043, 126613, 136509, 142019, 147449, 183981, 186889, 200183, 204219, 214819, 221101, 224123, 230977 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 LINKS EXAMPLE a(1)=2607 prime onwards: 10100010111110120120220233404122002310413505735162607. Case prime downwards is: 26073516505710413200234041222023310120120101000101111. CROSSREFS Cf. A054256, A054257. Sequence in context: A212083 A236889 A254695 * A236666 A252341 A235777 Adjacent sequences:  A054255 A054256 A054257 * A054259 A054260 A054261 KEYWORD nonn,base AUTHOR Patrick De Geest, Feb 15 2000. STATUS approved

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Last modified December 10 17:12 EST 2018. Contains 318049 sequences. (Running on oeis4.)