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%I #18 Dec 12 2024 23:31:09
%S 2,11,23,103,113,223,2237,10007,10193,-1,11113,22273,100003,166931,-1,
%T -1,111119,222323,1000003,1367777,-1,-1,-1,1111711,2222273,10000019,
%U 13334117,-1,-1,-1,-1,11111117,22222223,100000007,110499911,-1,-1,-1,-1,-1,111111113,222222227
%N Table T(n,k), 0 < n and 0 <= k < n, where the n-th row contains the smallest n-digit primes that remain prime even if any k of their digits are deleted, or -1 if no such prime exists.
%e Row 2 contains 11 and 23 because 11 remains prime if any 0 of its digits are deleted, and 23 remains prime if any 1 of its digits is deleted, and no lesser 2-digit prime has this property.
%e Table begins:
%e 2;
%e 11, 23;
%e 103, 113, 223;
%e 1009, 1013, 1117, 2237;
%e 10007, 10193, -1, 11113, 22273;
%e 100003, 166931, -1, -1, 111119, 222323;
%e 1000003, 1367777, -1, -1, -1, 1111711, 2222273;
%e 10000019, 13334117, -1, -1, -1, -1, 11111117, 22222223;
%e ...
%Y Cf. A003617, A019546, A051362, A378081, A378563.
%K sign,base,tabl,new
%O 1,1
%A _Jean-Marc Rebert_, Dec 04 2024