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A255578
Carmichael numbers of the form (12*k+1)*(24*k+1)*(36*k+1)*(72*k+1), where 12*k+1, 24*k+1, 36*k+1 and 72*k+1 are all primes.
2
461574735553, 84154807001953, 973694665856161, 3060522900274753, 11861640972220321, 386096840467598593, 2322064552169233153, 7545246852649391713, 9688364125836900193, 10972742858243841313, 11660828668219467073, 16553878978808515681, 17905475062325518273
OFFSET
1,1
LINKS
Umberto Cerruti, Pseudoprimi di Fermat e numeri di Carmichael (in Italian), p. 14.
PROG
(Magma) [(12*n+1)*(24*n+1)*(36*n+1)*(72*n+1): n in [1..4000] | IsPrime(12*n+1) and IsPrime(24*n+1) and IsPrime(36*n+1) and IsPrime(72*n+1)];
CROSSREFS
Sequence in context: A289111 A364785 A209833 * A239921 A250867 A104303
KEYWORD
nonn
AUTHOR
Vincenzo Librandi, Feb 26 2015
STATUS
approved