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A050666 Primes p such that number of primes produced according to rules stipulated in Honaker's A048853 is 4. 1
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..41.

EXAMPLE

Altering a(1)=97 gives 4 primes: 17, 37, 47 and 67.

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-Fran├žois Alcover, May 09 2017 *)

CROSSREFS

Cf. A048853, A050673, A050655.

Sequence in context: A105128 A031927 A174338 * A160440 A107213 A157331

Adjacent sequences:  A050663 A050664 A050665 * A050667 A050668 A050669

KEYWORD

nonn,base

AUTHOR

Patrick De Geest, Jul 15 1999

STATUS

approved

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Last modified October 22 07:06 EDT 2021. Contains 348160 sequences. (Running on oeis4.)