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A244990 After 1, numbers whose greatest prime factor is a prime with an even index; n such that A061395(n) is even. 8
1, 3, 6, 7, 9, 12, 13, 14, 18, 19, 21, 24, 26, 27, 28, 29, 35, 36, 37, 38, 39, 42, 43, 48, 49, 52, 53, 54, 56, 57, 58, 61, 63, 65, 70, 71, 72, 74, 76, 78, 79, 81, 84, 86, 87, 89, 91, 95, 96, 98, 101, 104, 105, 106, 107, 108, 111, 112, 113, 114, 116, 117, 122, 126, 129, 130, 131, 133, 139, 140, 142, 143, 144 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Equally, after 1, natural numbers n such that A006530(n) is in A031215.

A122111 maps each one of these numbers to a unique term of A028260 and vice versa.

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..10001

FORMULA

For all n, A244988(a(n)) = n.

PROG

(Scheme, with Antti Karttunen's IntSeq-library)

(define A244990 (MATCHING-POS 1 1 (COMPOSE even? A061395)))

CROSSREFS

Complement: A244991.

Cf. A006530, A028260, A031215, A061395, A122111, A244988, A244321, A244322.

Sequence in context: A188971 A176065 A135412 * A191990 A289059 A286686

Adjacent sequences:  A244987 A244988 A244989 * A244991 A244992 A244993

KEYWORD

nonn

AUTHOR

Antti Karttunen, Jul 21 2014

STATUS

approved

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Last modified January 18 13:09 EST 2019. Contains 319271 sequences. (Running on oeis4.)