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A375875
Smallest n-bit Carmichael number, or 0 if no such number exists.
0
561, 1105, 2465, 6601, 8911, 29341, 41041, 75361, 162401, 278545, 530881, 1050985, 2100901, 4335241, 8719309, 16778881, 33596641, 67371265, 134809921, 270857521, 540066241, 1074363265, 2159003281, 4295605861, 8612234401, 17190510961, 34364331001, 68910004801, 137691502081, 274895715601, 549813672001, 1099910311201
OFFSET
10,1
COMMENTS
a(n) > 0 for large enough n, see Larsen link. Probably a(n) > 0 for all n >= 10.
LINKS
Daniel Larsen, Bertrand's Postulate for Carmichael Numbers, arXiv preprint (2021). arXiv:2111.06963 [math.NT]
FORMULA
a(n) ~ 2^n due to Larsen.
PROG
(PARI) a(n)=forsquarefree(t=2^(n-1), 2^n, my(f=t[2]); if(#f~>1 && f[1, 1]>2 && Korselt(t[1], f), return(t[1])))
CROSSREFS
Conjecturally a subsequence of A002997.
Sequence in context: A263403 A083733 A339869 * A214428 A262043 A264012
KEYWORD
nonn
AUTHOR
STATUS
approved