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%I #17 Jan 08 2024 14:30:19
%S 4,20,68,88,122,140,188,200,212,220,224,244,254,374,460,490,502,518,
%T 550,568,632,688,734,814,832,884,898,908,928,982,1022,1108,1472,1490,
%U 1498,1514,1544,1580,1894,1954,2074,2230,2294,2384,2492,2524,2722
%N Indices n for which concatenation of the numbers from n to n + 9 is prime.
%H Robert Israel, <a href="/A287244/b287244.txt">Table of n, a(n) for n = 1..10000</a>
%H F. Smarandache, <a href="http://www.gallup.unm.edu/~smarandache/Sequences-book.pdf">Sequences of Numbers Involved in Unsolved Problems</a>.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/SmarandacheSequences.html">Smarandache Sequences</a>
%e a(1) = 4, since 45678910111213 is prime.
%p filter:= proc(n) isprime(parse(cat($n .. n+9))) end proc:
%p select(filter, 2*[$1..10^4]); # _Robert Israel_, Jan 08 2024
%t Position[Map[FromDigits@ Flatten@ IntegerDigits@ # &, Partition[Range@ 2800, 10, 1]], p_ /; PrimeQ@ p][[All, 1]] (* _Michael De Vlieger_, May 22 2017 *)
%Y Cf. A030458.
%K base,easy,nonn
%O 1,1
%A _XU Pingya_, May 22 2017
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