OFFSET
1,1
COMMENTS
Rigidly-deletable primes are deletable primes where the choice of digit to delete is unique (all other choices give nonprime numbers).
LINKS
Arkadiusz Wesolowski, Table of n, a(n) for n = 1..10000
Chris Caldwell, The Prime Glossary, Deletable prime
Carlos Rivera, Puzzle 138. Deletable primes, The Prime Puzzles and Problems Connection.
EXAMPLE
103 is a member since removing a digit will either give 03 which has a leading zero, or give one of the numbers 13 or 10. 2017 is not a member since removing a digit will either give 017 which has a leading zero, or give one of the numbers 217, 207, or 201, which are all composite. - Arkadiusz Wesolowski, Nov 27 2021
MATHEMATICA
lst1 = {}; Do[If[PrimeQ[n], p = n; Label[begin]; lst2 = {}; Do[i = IntegerDigits[p]; c = FromDigits@Drop[i, {d}]; If[Length[i] - 1 == IntegerLength[c], AppendTo[lst2, c]], {d, IntegerLength@p}]; t = Select[lst2, PrimeQ[#] &]; If[Length[t] == 1, p = FromDigits[t]; Goto[begin]]; If[IntegerLength[p] == 1, AppendTo[lst1, n]]], {n, 2671}]; lst1 (* Arkadiusz Wesolowski, Feb 22 2013 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Arkadiusz Wesolowski, Apr 11 2011
EXTENSIONS
Name clarified by Arkadiusz Wesolowski, Nov 27 2021
STATUS
approved