A101997 16n-1 such that 4n-1, 8n-1, 16n-1, 32n-1 and 64n-1 are primes.

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

Offset

1,1

Links

Table of n, a(n) for n=1..25.

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