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A268381 Numbers having at least the same number of prime factors of the form 4*k+1 than of the form 4*k+3, when counted with multiplicity. 5
1, 2, 4, 5, 8, 10, 13, 15, 16, 17, 20, 25, 26, 29, 30, 32, 34, 35, 37, 39, 40, 41, 50, 51, 52, 53, 55, 58, 60, 61, 64, 65, 68, 70, 73, 74, 75, 78, 80, 82, 85, 87, 89, 91, 95, 97, 100, 101, 102, 104, 106, 109, 110, 111, 113, 115, 116, 119, 120, 122, 123, 125, 128, 130, 136, 137, 140, 143, 145, 146, 148, 149, 150 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Numbers n for which A083025(n) >= A065339(n) or equally, for which A079635(n) >= 0.

Closed under multiplication.

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..10000

MATHEMATICA

Position[Array[Map[Length, {Select[#, Mod[#, 4] == 1 &], Select[#, Mod[#, 4] == 3 &]}] &@ Flatten@ Apply[Table[#1, {#2}] &, FactorInteger@ #, 1] &, {150}], {a_, b_} /; a >= b] // Flatten (* Michael De Vlieger, Feb 05 2016 *)

PROG

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

(define A268381 (MATCHING-POS 1 1 (COMPOSE not negative? A079635)))

CROSSREFS

Complement: A268380.

Disjoint union of A072202 and A268379.

Cf. A079635, A065339, A083025.

Sequence in context: A173509 A007729 A174868 * A186349 A304360 A072437

Adjacent sequences:  A268378 A268379 A268380 * A268382 A268383 A268384

KEYWORD

nonn

AUTHOR

Antti Karttunen, Feb 05 2016

STATUS

approved

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Last modified May 24 04:25 EDT 2019. Contains 323528 sequences. (Running on oeis4.)