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A113928 (RSA-768)+10^n = prime where RSA-768 is the 232 decimal digit RSA challenge number. 0
70, 129, 178, 263, 337, 545, 708, 714, 867, 1317, 1587, 1961, 19415 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

This sequence shows that the difference between a composite number and a prime rests on the modification of a single decimal digit of the given composite number.

LINKS

Table of n, a(n) for n=1..13.

EXAMPLE

(RSA-768) + 10^70 is prime.

MATHEMATICA

Position[PrimeQ[Table[ \

123018668453011775513049495838496272077285356959533479219732245215172640050726\

365751874520219978646938995647494277406384592519255732630345373154826850791702\

6122142913461670429214311602221240479274737794080665351419597459856902143413 \

+ 10^n, {n, 1232}]], True]

PROG

(PARI) \\ Set N to RSA-768

for(n=1, 1e5, if(ispseudoprime(N+10^n), print1(n", "))) \\ Charles R Greathouse IV, Oct 03 2011

CROSSREFS

Sequence in context: A024748 A024756 A254367 * A160354 A215111 A255801

Adjacent sequences:  A113925 A113926 A113927 * A113929 A113930 A113931

KEYWORD

nonn

AUTHOR

Joao Carlos Leandro da Silva (zxawyh66(AT)yahoo.com), Jan 30 2006

EXTENSIONS

a(10)-a(12) from Charles R Greathouse IV, Oct 03 2011

a(13) from Charles R Greathouse IV, Oct 05 2011

No more terms below 30,000.

STATUS

approved

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Last modified December 9 03:14 EST 2021. Contains 349625 sequences. (Running on oeis4.)