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A114429 Larger of the greatest twin prime pair with n digits. 2
7, 73, 883, 9931, 99991, 999961, 9999973, 99999589, 999999193, 9999999703, 99999999763, 999999999961, 9999999998491, 99999999999973, 999999999997969, 9999999999999643, 99999999999998809, 999999999999998929 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Also the denominator of the largest prime over prime fraction less than 10^n.

LINKS

Abhiram R Devesh, Table of n, a(n) for n = 1..100

PROG

(Python)

import sympy

for i in range(1, 100):

....a=(10**i)

....p=sympy.prevprime(a)

....while sympy.isprime(p-2)==False:

........p=sympy.prevprime(p)

....print(p)

## Abhiram R Devesh, Aug 02 2014

(PARI)

a(n)=p=precprime(10^n); while(!ispseudoprime(p-2), p=precprime(p-1)); return(p)

vector(50, n, a(n)) \\ Derek Orr, Aug 02 2014

CROSSREFS

Sequence in context: A099141 A084768 A106651 * A124547 A084363 A050352

Adjacent sequences:  A114426 A114427 A114428 * A114430 A114431 A114432

KEYWORD

base,easy,nonn

AUTHOR

Cino Hilliard, Feb 13 2006

EXTENSIONS

Corrected by T. D. Noe, Nov 15 2006

STATUS

approved

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Last modified April 30 16:28 EDT 2017. Contains 285670 sequences.