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A061671 Numbers n such that { x +- 2^k : 0 < k < 4 } are primes, where x = 210*n - 105. 3
1, 77, 93, 209, 5197, 7695, 9307, 13442, 13524, 15445, 16192, 28600, 30970, 34228, 36388, 38391, 41625, 50127, 52795, 55546, 69146, 70538, 70642, 70747, 76314, 76642, 90079, 91416, 93496, 94288, 95773, 96415, 101530, 104049, 107559, 118031 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

This sequence does not include the sextet (7,11,13,17,19,23). It is a proper subset of A014561 in a certain sense.

REFERENCES

G. H. Hardy and E. M. Wright, An Introduction to the Theory of Numbers, 5th ed., Oxford Univ. Press, 1979, conjectures following th. 5

LINKS

F. Ellermann, Illustration for A002110, A005867, A038110, A060753

EXAMPLE

16057, 16061, 16063, 16067, 16069, 16073 are prime and (16065+105)/210= 77= a(2).

MATHEMATICA

Select[Range[1, 1000000], Union[PrimeQ[(210*# - 105) + {-8, -4, -2, 2, 4, 8}]] == {True} &]

CROSSREFS

210 = 7*5*3*2 = A002110(4), cf. A014561.

Sequence in context: A052202 A089525 A154534 * A064902 A127335 A193570

Adjacent sequences:  A061668 A061669 A061670 * A061672 A061673 A061674

KEYWORD

nonn

AUTHOR

Frank.Ellermann(AT)t-online.de, Jun 16 2001

EXTENSIONS

More terms from Larry Reeves (larryr(AT)acm.org), Jun 20 2001 and from Frank.Ellermann(AT)t-online.de, Nov 26, 2001. Mathematica script from Peter Bertok (peter(AT)bertok.com), Nov 27 2001.

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Last modified February 14 16:32 EST 2012. Contains 205635 sequences.