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A067267
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n, 10*n+1, 10*n+3, 10*n+7 and 10*n+9 are all prime.
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0
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19, 6949, 10111, 15727, 20149, 24799, 26041, 26881, 29587, 29947, 40213, 41203, 44257, 46747, 47701, 49057, 50023, 51061, 55921, 66109, 66643, 73939, 76819, 79579, 95947, 106501, 110083, 111781, 112213, 114679
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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EXAMPLE
| a(1)=19 because 191, 193, 197 and 199 are all prime.
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MATHEMATICA
| okQ[n_]:=Module[{n10=10n}, And@@PrimeQ[{n10+1, n10+3, n10+7, n10+9}]]
Select[Prime[Range[20000]], okQ] [from Harvey P. Dale, Dec. 13, 2010]
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CROSSREFS
| Cf. A007811.
Sequence in context: A172662 A201303 A013724 * A124989 A156973 A093400
Adjacent sequences: A067264 A067265 A067266 * A067268 A067269 A067270
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KEYWORD
| nonn
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AUTHOR
| Sudipta Das (juitech(AT)vsnl.net), Feb 21 2002
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