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A108897 Numbers n such that 60n^2 + 30n - 30 +- 1 is a twin prime pair. 1
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 21, 22, 37, 39, 40, 41, 42, 51, 53, 54, 59, 64, 71, 80, 82, 83, 94, 102, 103, 105, 106, 110, 114, 118, 128, 143, 144, 156, 166, 167, 169, 172, 183, 192, 193, 199, 218, 222, 224, 227, 234, 235, 236, 253, 258, 259, 265, 266 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Some consecutive terms in this sequence are (102:103), (105:106), (143:144), ... (1320071:1320072), (1320250:1320251) ... Conjecture: There are infinitely many of these consecutive pairs.

REFERENCES

D. Wells, Prime Numbers: The Most Mysterious Figures in Math, John Wiley & Sons, 2005, p. 231.

LINKS

Table of n, a(n) for n=1..61.

MATHEMATICA

lst={}; Do[If[PrimeQ[60*n^2+30*n-30-1]&&PrimeQ[60*n^2+30*n-30+1], AppendTo[lst, n]], {n, 10^3}]; lst (* Vladimir Joseph Stephan Orlovsky, Aug 08 2008 *)

CROSSREFS

Sequence in context: A151767 A213517 A173899 * A023767 A023794 A032948

Adjacent sequences:  A108894 A108895 A108896 * A108898 A108899 A108900

KEYWORD

easy,nonn

AUTHOR

Jason Earls, Jul 16 2005

STATUS

approved

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Last modified May 24 14:49 EDT 2019. Contains 323532 sequences. (Running on oeis4.)