A084375
Indices of primes which remain prime if any one digit is deleted (leading zeros allowed).
Original entry on oeis.org
9, 12, 16, 21, 30, 32, 33, 40, 41, 45, 64, 66, 83, 113, 128, 170, 173, 184, 239, 302, 333, 341, 446, 555, 657, 804, 903, 942, 1194, 1252, 1295, 1345, 2258, 2652, 2943, 3246, 3926, 4205, 4939, 7243, 7318, 8716, 8864, 9028, 9103, 10594, 15249, 28712, 30451
Offset: 1
The 41st prime is 179, and 17, 19, and 79 are all primes, so 41 is in the sequence. - _Harvey P. Dale_, Jun 20 2011
A378697
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.
Original entry on oeis.org
2, 11, 23, 103, 113, 223, 2237, 10007, 10193, -1, 11113, 22273, 100003, 166931, -1, -1, 111119, 222323, 1000003, 1367777, -1, -1, -1, 1111711, 2222273, 10000019, 13334117, -1, -1, -1, -1, 11111117, 22222223, 100000007, 110499911, -1, -1, -1, -1, -1, 111111113, 222222227
Offset: 1
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.
Table begins:
2;
11, 23;
103, 113, 223;
1009, 1013, 1117, 2237;
10007, 10193, -1, 11113, 22273;
100003, 166931, -1, -1, 111119, 222323;
1000003, 1367777, -1, -1, -1, 1111711, 2222273;
10000019, 13334117, -1, -1, -1, -1, 11111117, 22222223;
...
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