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%I #9 Jul 21 2017 13:09:48
%S 3,7,17,23,41,89,113,131,137,163,179,193,271,281,283,337,389,431,443,
%T 457,479,587,593,613,661,673,683,691,727,739,757,787,809,829,863,883,
%U 907,983,1009,1051,1087,1123,1153,1163,1181,1213,1229,1249,1279,1297
%N Primes whose "Look And Say" descriptions from left to right (in the sense of method B, i.e., digit-indication followed by frequency) are also primes.
%e 41, 337, 809, 1123, for instance, are in the sequence because their respective descriptions 4111 (4 once, 1 once), 3271 (3 twice, 7 once), 810191 (8 once, 0 once, 9 once), 122131 (1 twice, 2 once, 3 once) are also primes.
%t LookAndSayB[ n_] := FromDigits@Flatten@((Through[ {First, Length}[ # ] ] &) /@ Split@IntegerDigits@n); Select[Prime@Range[215], PrimeQ@LookAndSayB@# &] (* _Ray Chandler_, Jan 08 2007 *)
%Y Cf. A007651, A056815, A127176.
%K base,nonn
%O 1,1
%A _Lekraj Beedassy_, Jan 07 2007
%E Corrected by _Ray Chandler_, Jan 08 2007
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