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A182381 Carmichael numbers divisible by 17 and 29. 1
2465, 278545, 13696033, 75151441, 93869665, 169570801, 490099681, 612347905, 707926801, 744866305, 1190790721, 1321983937, 1913016001, 2159003281, 2176838049, 2232385345, 2353639681, 3880251649, 4059151489, 4314912001, 5204110465, 8355729313, 8548543585, 9584174881, 10054063041, 10933377841 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Conjecture: Any Carmichael number C divisible by 17 and 29 can be written as C = 952*n + 561; checked up to the Carmichael number 105823343809.

Note: the number 561 is the first Carmichael number and the number 952 comes from the following interesting relation: 952^2 = 1105^2 - 561^2 (where 1105 is the second Carmichael number).

The conjecture follows from Korselt's criterion. More is true: a(n) = 2465 mod 55216. - Charles R Greathouse IV, Oct 02 2012

LINKS

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

E. W. Weisstein, Carmichael Number

PROG

(PARI) Korselt(n)=my(f=factor(n)); for(i=1, #f[, 1], if(f[i, 2]>1||(n-1)%(f[i, 1]-1), return(0))); 1

list(lim)=my(v=List()); forstep(n=2465, lim, 55216, if(Korselt(n), listput(v, n))); Vec(v) \\ Charles R Greathouse IV, Jun 30 2017

CROSSREFS

Sequence in context: A236707 A304554 A152497 * A284089 A252113 A102689

Adjacent sequences:  A182378 A182379 A182380 * A182382 A182383 A182384

KEYWORD

nonn

AUTHOR

Marius Coman, Apr 27 2012

EXTENSIONS

Terms corrected by Charles R Greathouse IV, Oct 02 2012

STATUS

approved

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Last modified July 18 15:44 EDT 2019. Contains 325144 sequences. (Running on oeis4.)