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A221794
Number of primes of the form (x+1)^3 - x^3 with x <= 10^n.
5
1, 7, 42, 263, 1965, 15282, 126826
OFFSET
0,2
COMMENTS
Cuban primes are primes that are the difference of two consecutive cubes, p = (x+1)^3 - x^3 (A002407). They are also primes of the form 3k(k+1) + 1, where values for k+1 are in A002504.
CROSSREFS
Cf. A002407, A002504, A003215, A113478 (number of cuban primes < 10^n).
Sequence in context: A127016 A152239 A152240 * A187246 A278152 A366222
KEYWORD
nonn
AUTHOR
Vladimir Pletser, Jan 25 2013
STATUS
approved