

A106092


Even numbers and primes.


2



2, 3, 4, 5, 6, 7, 8, 10, 11, 12, 13, 14, 16, 17, 18, 19, 20, 22, 23, 24, 26, 28, 29, 30, 31, 32, 34, 36, 37, 38, 40, 41, 42, 43, 44, 46, 47, 48, 50, 52, 53, 54, 56, 58, 59, 60, 61, 62, 64, 66, 67, 68, 70, 71, 72, 73, 74, 76, 78, 79, 80, 82, 83, 84, 86, 88, 89, 90, 92, 94, 96, 97
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OFFSET

1,1


LINKS

Robert Israel, Table of n, a(n) for n = 1..10000
Paulo A. Martin, The Galois group of x^nx^(n1)...x1, Journal of Pure and Applied Algebra, Volume 190, Issues 13, 1 June 2004, Pages 213223.


FORMULA

From Robert Israel, Jan 01 2019: (Start)
a(k1+A000720(2*k)] = 2*k.
a((prime(k)3)/2 + k] = prime(k) for k >= 2. (End)


MAPLE

map(op, [seq([2*k, `if`(isprime(2*k+1), 2*k+1, NULL)], k=1..100)]); # Robert Israel, Jan 01 2019


MATHEMATICA

Union[Prime[Range[30]], Select[Range[113], EvenQ]]
DeleteCases[Range[2, 100], _?(OddQ[#]&&CompositeQ[#]&)] (* Harvey P. Dale, Dec 04 2021 *)


PROG

(PARI) isok(n) = isprime(n)  ((n%2) == 0); \\ Michel Marcus, Feb 24 2020


CROSSREFS

Cf. A000720.
Complement of A014076.
Sequence in context: A307646 A246786 A095949 * A210940 A257500 A121208
Adjacent sequences: A106089 A106090 A106091 * A106093 A106094 A106095


KEYWORD

nonn


AUTHOR

Zak Seidov, May 07 2005


STATUS

approved



