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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Intersection of A002997 and A308643.

Intersection of A002997 and A036844.

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..1377 (terms below 2^64)

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

Cf. A002997, A001414, A036844, A046347, A308643.

Sequence in context: A198298 A074773 A340133 * A251523 A155961 A282401

Adjacent sequences:  A309000 A309001 A309002 * A309004 A309005 A309006

KEYWORD

nonn

AUTHOR

David James Sycamore, Jul 05 2019

STATUS

approved

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Last modified July 23 11:52 EDT 2021. Contains 346259 sequences. (Running on oeis4.)