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A299643 Primes of the form 2^k + 5*k. 2
7, 23, 163, 557, 32843, 2097257, 8589934757, 137438953657, 2305843009213694257, 2787593149816327892691964784081045188248257, 730750818665451459101842416358141509827966272283, 862718293348820473429344482784628181556388621521298319395315527976057 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Primes in A297663.

LINKS

Table of n, a(n) for n=1..12.

EXAMPLE

2^1 + 5*1 = 2 + 5 = 7 is prime.

2^3 + 5*3 = 8 + 15 = 23 is prime.

2^7 + 5*7 = 128 + 35 = 163 is prime.

MAPLE

select(isprime, [seq(2^k + 5*k, k=0..300)]); # Muniru A Asiru, Mar 04 2018

MATHEMATICA

Select[Table[2^n + 5 n, {n, 0, 300}], PrimeQ]

PROG

(MAGMA) [a: n in [0..450] | IsPrime(a) where a is 2^n + 5*n ];

(PARI) lista(nn) = for(k=1, nn, if(isprime(p=2^k + 5*k), print1(p, ", "))); \\ Altug Alkan, Mar 03 2018

(GAP) Filtered(List([1..300], k->2^k + 5*k), IsPrime); # Muniru A Asiru, Mar 04 2018

CROSSREFS

Cf. A297663.

Sequence in context: A056205 A099051 A187487 * A034192 A050918 A322557

Adjacent sequences:  A299640 A299641 A299642 * A299644 A299645 A299646

KEYWORD

nonn

AUTHOR

Vincenzo Librandi, Feb 28 2018

EXTENSIONS

a(12) from Muniru A Asiru, Mar 04 2018

STATUS

approved

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Last modified January 26 10:40 EST 2020. Contains 331279 sequences. (Running on oeis4.)