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%I #10 Feb 03 2019 18:24:13
%S 571,113,131,317,719,293,313,137,347,359,167,677,173,379,983,389,997,
%T 971,101,11,103,31,107,71,109,911,113,131,127,271,131,311,113,137,139,
%U 149,491,151,157,571,163,631,167,173,317,179,181,811,191,911,193,197
%N Take A000040, omit commas: 23571113171923..., select primes seen when scanning three consecutive digits from left.
%C Because leading zeroes are permitted, some of the terms have less than three digits. The first single-digit term is a(371). - _Harvey P. Dale_, Feb 03 2019
%e In the sequence 2357111317192329... (primes without delimiters) 3-digit primes are: 571, 113, 131, 317,
%t p200=Flatten[IntegerDigits[Prime[Range[200]]]]; n=3; (* n-digit primes!*) pn=Partition[p200, n, 1]; ln=Length[pn]; tab=Table[Sum[10^(n-k)*pn[[i, k]], {k, n}], {i, ln}]; Select[tab, PrimeQ]
%t Select[FromDigits/@Partition[Flatten[IntegerDigits/@Prime[ Range[ 50]]],3,1],PrimeQ] (* _Harvey P. Dale_, Feb 03 2019 *)
%K easy,nonn,base
%O 1,1
%A _Zak Seidov_, Aug 22 2002
%E Definition clarified by _Harvey P. Dale_, Feb 03 2019
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