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A237990 Numbers m such that the numbers of primes, even positive integers and odd positive integers less than or equal to m are all even. 2
4, 8, 16, 20, 40, 44, 56, 64, 72, 80, 92, 96, 108, 116, 120, 124, 132, 136, 140, 144, 148, 152, 156, 164, 176, 184, 188, 196, 200, 204, 208, 224, 232, 240, 252, 256, 264, 268, 272 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A subsequence of A008586.

LINKS

Ivan N. Ianakiev, Table of n, a(n) for n = 1..10000

FORMULA

a(n) == 0 (mod 4)

EXAMPLE

A tetrahedral die whose faces are marked with the numbers from 1 to 4 has an even number of sides marked with prime numbers, even integers and odd integers. Therefore, 4 is in the sequence.

CROSSREFS

Cf. A008586, A237989.

Sequence in context: A181471 A272753 A272804 * A312807 A312808 A249486

Adjacent sequences:  A237987 A237988 A237989 * A237991 A237992 A237993

KEYWORD

nonn,easy

AUTHOR

Ivan N. Ianakiev, Feb 16 2014

STATUS

approved

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Last modified October 18 04:57 EDT 2019. Contains 328145 sequences. (Running on oeis4.)