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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 A321837 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 July 21 07:23 EDT 2019. Contains 325192 sequences. (Running on oeis4.)