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A133281 Numbers k such that k + googol is a lower twin prime. 3
35737, 58291, 59257, 63361, 87079, 138277, 141979, 175831, 178897, 219979, 365491, 394681, 413497, 503209, 558187, 599197, 655051, 730321, 747751, 757189, 763369, 788617, 831079, 861331, 865417, 870247, 900199, 947881, 1038217, 1081801, 1131037, 1165201, 1182229 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

For k > 219979, k + a googol is a probable prime.

For each of the 28 terms listed, the Magma Calculator (http://magma.maths.usyd.edu.au/calc/) verified that both 10^100 + a(n) and 10^100 + a(n) + 2 were prime. - Jon E. Schoenfield, Aug 24 2009

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..1000

FORMULA

Googol = 10^100.

MATHEMATICA

Select[Range[10^6], And @@ PrimeQ[10^100 + # + {0, 2}] &] (* Amiram Eldar, Dec 26 2019 *)

PROG

(PARI) googol(n) = { local(x, a, j); x=10^100; forstep(j=1, 1000000, 2, a=x+j; if(ispseudoprime(a)&ispseudoprime(a+2), print1(j", "); ); ) }

CROSSREFS

Cf. A001097, A001359, A006512, A133282.

Sequence in context: A156405 A065611 A101252 * A326320 A216065 A236201

Adjacent sequences:  A133278 A133279 A133280 * A133282 A133283 A133284

KEYWORD

nonn

AUTHOR

Cino Hilliard, Oct 13 2007

EXTENSIONS

More terms from Amiram Eldar, Dec 26 2019

STATUS

approved

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Last modified June 20 09:30 EDT 2021. Contains 345162 sequences. (Running on oeis4.)