A220432 Numbers not divisible by 2, 3 or any prime of the form 4x^2+2xy+7y^2 (see A219908).

1, 5, 11, 17, 19, 23, 25, 29, 31, 37, 41, 43, 47, 53, 55, 59, 61, 67, 71, 83, 85, 89, 95, 97, 101, 103, 107, 109, 113, 115, 121, 125, 127, 131, 137, 139, 145, 149, 155, 157, 167, 173, 179, 181, 185, 187, 191, 197, 199, 205, 209, 215, 223, 227, 229, 233, 235

Offset

1,2

Comments

Note that Jagy omitted 19.

Links

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

W. C. Jagy, Problem 11539, Amer. Math. Monthly, 119 (2012), 884-885.

Prog

(Haskell)
a220432 n = a220432_list !! (n-1)
a220432_list = filter (\x -> null $
   intersect (a027748_row x) (takeWhile (<= x) a219908_list)) a007310_list
-- Reinhard Zumkeller, Dec 15 2012

Crossrefs

Cf. A219907, A219908.

Cf. a027748, subsequence of A007310.

Sequence in context: A077130 A119754 A239127 * A266420 A317048 A081717

Adjacent sequences: A220429 A220430 A220431 * A220433 A220434 A220435

Keyword

nonn

Author

N. J. A. Sloane, Dec 15 2012

Extensions

Data fixed and extended by Reinhard Zumkeller, Dec 15 2012

Status

approved