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A113931 (RSA-1536)-10^n = prime where RSA-1536 is the 463 decimal digit unfactored RSA challenge number. 0
84, 99, 564 (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..3.

EXAMPLE

(RSA-1536)-10^84 = prime

MATHEMATICA

Position[PrimeQ[Table[ \

184769970321174147430683562020016440301854933866341017147178577491065169671116\

124985933768430543574458561606154457179405222971773252466096064694607124962372\

044202226975675668737842756238950876467844093328515749657884341508847552829818\

672645133986336493190808467199043187438128336350279547028265329780293491615581\

188104984490831954500984839377522725705257859194499387007369575568843693381277\

9613089230392569695253261620823676490316036551371447913932347169566988069 - \

10^n, {n, 1463}]], True]

PROG

(PARI) \\ Set N to RSA-1536

for(n=1, 463, if(ispseudoprime(N-10^n), print1(n", ")))

CROSSREFS

Sequence in context: A219183 A289218 A329182 * A214866 A111313 A157119

Adjacent sequences:  A113928 A113929 A113930 * A113932 A113933 A113934

KEYWORD

nonn,bref,base,fini,full

AUTHOR

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

STATUS

approved

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Last modified June 20 10:07 EDT 2021. Contains 345162 sequences. (Running on oeis4.)