OFFSET
1,1
COMMENTS
We got Carmichael numbers for n = 1, 5, 25, 49, 325, 1421, 2161, 2245, 10465, 18205, 22685, 25345, 34433, 36205, 37765, 38129, 42645, 89565, 104173, 119509, 134725, 186101.
Conjecture: Any Carmichael number C divisible by 37 and 73 can be written as C = 37*73*(18n+91), where n is natural; checked for the first 22 Carmichael numbers divisible by 37 and 73.
This follows from Korselt's criterion. More is true: such numbers are 37*73*(72k+1). - Charles R Greathouse IV, Oct 02 2012
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
Eric Weisstein's World of Mathematics, 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=294409, lim, 194472, if(Korselt(n), listput(v, n))); Vec(v) \\ Charles R Greathouse IV, Jun 30 2017
CROSSREFS
KEYWORD
nonn
AUTHOR
Marius Coman, Apr 18 2012
EXTENSIONS
Terms corrected by Charles R Greathouse IV, Oct 02 2012
STATUS
approved