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A281940
Least k such that k^n + 1 is the product of n distinct primes (k > 0).
3
1, 3, 9, 43, 46, 47, 245, 1697, 109, 565, 3938, 3255, 30089, 18951, 2217
OFFSET
1,2
COMMENTS
Corresponding values of k^n + 1 are 2, 10, 730, 3418802, 205962977, 10779215330, ...
EXAMPLE
a(3) = 9 because 9^3 + 1 = 2 * 5 * 73 and 9 is the least number with this property.
PROG
(PARI) a(n) = my(k=1); while (!issquarefree(k^n+1) || omega(k^n+1) != n, k++); k;
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Altug Alkan, Feb 24 2017
EXTENSIONS
a(14)-a(15) from Giovanni Resta, Mar 10 2017
STATUS
approved