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A309003
Carmichael numbers divisible by the sum of their prime factors, sopfr (A001414).
1
3240392401, 13577445505, 14446721521, 84127131361, 203340265921, 241420757761, 334797586201, 381334973041, 461912170321, 1838314142785, 3636869821201, 10285271821441, 17624045440981, 18773053896961, 20137015596061, 24811804945201, 26863480687681, 35598629998801
OFFSET
1,1
COMMENTS
Intersection of A002997 and A308643.
Intersection of A002997 and A036844.
EXAMPLE
3240392401 = 29*37*41*73*1009, A001414(3240392401)=1189 = 29*41.
PROG
(PARI) sopfr(f) = f[, 1]~*f[, 2];
isCarmichael(n, f)= bittest(n, 0) && !for(i=1, #f~, (f[i, 2]==1 && n%(f[i, 1]-1)==1)||return) && (#f~>1);
isok(n) = my(f=factor(n)); isCarmichael(n, f) && !(n % sopfr(f)); \\ Michel Marcus, Jul 07 2019
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved