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%I #21 Aug 23 2016 08:07:42
%S 2,23,337,4447,55579,666667,7777801,88888901,1000000007,
%T 10101010101010101073,1111111111111111111189,121212121212121212121327,
%U 13131313131313131313131439,1414141414141414141414141451,151515151515151515151515151607,16161616161616161616161616161709,1717171717171717171717171717171741
%N Next prime after concatenate of n, n times (A000461).
%H Dana Jacobsen, <a href="/A276025/b276025.txt">Table of n, a(n) for n = 1..332</a> (last entry has 996 digits)
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/NextPrime.html">Next Prime</a>.
%F a(n) = A007918(A000461(n)).
%F a(n) = A000040(A000720(A000461(n))+1).
%e a(5) = 55579, since this is the next prime after 55555.
%p a:= n-> nextprime(parse(cat(n$n))):
%p seq(a(n), n=1..20); # _Alois P. Heinz_, Aug 18 2016
%t Table[NextPrime[n ((10^(n Floor[Log[10, 10 n]]) - 1)/(10^Floor[Log[10, 10 n]] - 1)), Plus[1]], {n, 1, 17}]
%o (PARI) a000461(n) = my(i=1, k=n); while(i < n, k=eval(Str(k, n)); i++); k
%o a(n) = nextprime(a000461(n)) \\ _Felix Fröhlich_, Aug 18 2016
%o (Perl) use ntheory ":all"; sub a276025 { my $n=shift; next_prime("$n" x $n); } _Dana Jacobsen_, Aug 22 2016
%Y Cf. A000040, A000720, A000461, A007918.
%K nonn,base
%O 1,1
%A _Ilya Gutkovskiy_, Aug 16 2016
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