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 A101997 16n-1 such that 4n-1, 8n-1, 16n-1, 32n-1 and 64n-1 are primes. 5
 719, 214559, 253679, 507359, 508559, 1017119, 1184399, 1363679, 2429279, 3242159, 4276799, 4490639, 6394799, 6486479, 7283999, 7464959, 7650719, 7683839, 8181359, 8553599, 8631599, 8981279, 9112319, 9428879, 10671119 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS EXAMPLE 4*45-1=179, 8*45-1=359, 16*45-1=719, 32*45-1=1439 and 64*45-1=2879 are primes, so the first entry is 719. MATHEMATICA Select[With[{c=2^Range[2, 6]}, Table[c n-1, {n, 700000}]], AllTrue[#, PrimeQ]&][[All, 3]] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Nov 29 2018 *) CROSSREFS Cf. A101994, A101995, A101996, A101998, A101999. Sequence in context: A139177 A064980 A290120 * A139195 A269124 A267336 Adjacent sequences:  A101994 A101995 A101996 * A101998 A101999 A102000 KEYWORD easy,nonn AUTHOR Douglas Stones (dssto1(AT)student.monash.edu.au), Dec 23 2004 STATUS approved

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Last modified August 11 19:26 EDT 2022. Contains 356066 sequences. (Running on oeis4.)