A050666 Primes p such that number of primes produced according to rules stipulated in Honaker's A048853 is 4.
97, 389, 659, 743, 953, 2423, 2971, 3037, 3083, 3593, 3727, 4177, 4363, 4813, 4889, 5261, 5519, 5717, 5813, 5939, 6197, 6449, 7001, 7057, 7331, 7963, 8123, 8179, 8353, 8501, 8707, 9293, 9587, 10247, 11261, 13147, 14813, 15263, 16547, 17573, 18077
Offset: 1
Examples
Altering a(1)=97 gives 4 primes: 17, 37, 47 and 67.
Programs
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Mathematica
A048853[n_] := Module[{idn = IntegerDigits[n], id, np = 0}, Do[id = idn; If[id[[j]] != k, id[[j]] = k; If[id[[1]] != 0 && PrimeQ[FromDigits[id]], np = np + 1]], {j, 1, Length[idn]}, {k, 0, 9}]; np]; Select[Table[{p, A048853[p]}, {p, Prime[Range[3000]]}], #[[2]] == 4&][[All,1]] (* Jean-François Alcover, May 09 2017 *)