A224319
Primes without "1" as a digit that remain prime when any single digit is replaced with "1".
Original entry on oeis.org
37, 43, 47, 67, 73, 79, 337, 409, 439, 499, 607, 709, 3637, 3709, 4877, 6997, 7487, 9433, 76963, 334777
Offset: 1
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lst = {}; n = 1; Do[If[PrimeQ[p], i = IntegerDigits[p]; If[FreeQ[i, n], t = 0; s = IntegerLength[p]; Do[If[PrimeQ@FromDigits@Insert[Drop[i, {d}], n, d], t++, Break[]], {d, s}]; If[t == s, AppendTo[lst, p]]]], {p, 334777}]; lst
A224321
Primes without "7" as a digit that remain prime when any single digit is replaced with "7".
Original entry on oeis.org
2, 3, 5, 11, 13, 19, 31, 41, 43, 61, 109, 139, 251, 643, 4933, 9433, 36493, 191416111, 1304119699
Offset: 1
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lst = {}; n = 7; Do[If[PrimeQ[p], i = IntegerDigits[p]; If[FreeQ[i, n], t = 0; s = IntegerLength[p]; Do[If[PrimeQ@FromDigits@Insert[Drop[i, {d}], n, d], t++, Break[]], {d, s}]; If[t == s, AppendTo[lst, p]]]], {p, 36493}]; lst
Select[Prime[Range[4000]],DigitCount[#,10,7]==0&&AllTrue[FromDigits/@Table[ReplacePart[ IntegerDigits[#],n->7],{n,IntegerLength[#]}],PrimeQ]&] (* The program generates the first 17 terms of the sequence. *) (* Harvey P. Dale, Jun 09 2024 *)
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