A113932 - OEIS

%I #7 Oct 05 2011 08:52:25

%S 107,848,871,966,1110

%N (RSA-2048)-10^n = prime where RSA-2048 is the 617 decimal digit unfactored RSA challenge number.

%C 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 integer.

%e (RSA-2048)- 10^107 = prime

%t Position[PrimeQ[Table[ \

%t 251959084756578934940271832400483985714292821262040320277771378360436620207075\

%t 955562640185258807844069182906412495150821892985591491761845028084891200728449\

%t 926873928072877767359714183472702618963750149718246911650776133798590957000973\

%t 304597488084284017974291006424586918171951187461215151726546322822168699875491\

%t 824224336372590851418654620435767984233871847744479207399342365848238242811981\

%t 638150106748104516603773060562016196762561338441436038339044149526344321901146\

%t 575444541784240209246165157233507787077498171257724679629263863563732899121548\

%t 31438167899885040445364023527381951378636564391212010397122822120720357 - \

%t 10^n, {n, 1617}]], True]

%o (PARI) \\ Set N to RSA-2048

%o for(n=1, 617, if(ispseudoprime(N-10^n), print1(n", ")))

%K nonn,base,fini,full

%O 1,1

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