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Array read by rows: row n lists the first two primes with n digits.
2

%I #7 Mar 27 2021 14:06:55

%S 2,3,11,13,101,103,1009,1013,10007,10009,100003,100019,1000003,

%T 1000033,10000019,10000079,100000007,100000037,1000000007,1000000009,

%U 10000000019,10000000033,100000000003,100000000019,1000000000039,1000000000061

%N Array read by rows: row n lists the first two primes with n digits.

%t ftp[d_]:=Module[{np1=NextPrime[10^(d-1)]},{np1,NextPrime[np1]}]; Array[ ftp,15]//Flatten (* _Harvey P. Dale_, Mar 27 2021 *)

%Y Cf. A000040, A003617, A073914, A139053, A139054.

%K base,nonn,tabf

%O 1,1

%A _Omar E. Pol_, Apr 08 2008

%E More terms from _Sean A. Irvine_, Jun 02 2011