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A287244 Indices n for which concatenation of the numbers from n to n + 9 is prime. 2
4, 20, 68, 88, 122, 140, 188, 200, 212, 220, 224, 244, 254, 374, 460, 490, 502, 518, 550, 568, 632, 688, 734, 814, 832, 884, 898, 908, 928, 982, 1022, 1108, 1472, 1490, 1498, 1514, 1544, 1580, 1894, 1954, 2074, 2230, 2294, 2384, 2492, 2524, 2722 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
Eric Weisstein's World of Mathematics, Smarandache Sequences
EXAMPLE
a(1) = 4, since 45678910111213 is prime.
MAPLE
filter:= proc(n) isprime(parse(cat($n .. n+9))) end proc:
select(filter, 2*[$1..10^4]); # Robert Israel, Jan 08 2024
MATHEMATICA
Position[Map[FromDigits@ Flatten@ IntegerDigits@ # &, Partition[Range@ 2800, 10, 1]], p_ /; PrimeQ@ p][[All, 1]] (* Michael De Vlieger, May 22 2017 *)
CROSSREFS
Cf. A030458.
Sequence in context: A055538 A302317 A319779 * A344993 A123613 A006740
KEYWORD
base,easy,nonn
AUTHOR
XU Pingya, May 22 2017
STATUS
approved

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Last modified April 25 03:15 EDT 2024. Contains 371964 sequences. (Running on oeis4.)