login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A335593 Numbers k such that abs(A335592(k))/2 is prime. 4
4, 17, 27, 53, 74, 91, 97, 108, 111, 139, 152, 171, 207, 242, 245, 247, 275, 280, 286, 292, 310, 323, 352, 355, 385, 398, 424, 430, 471, 476, 484, 504, 525, 551, 555, 561, 586, 615, 626, 658, 659, 705, 709, 736, 744, 754, 772, 823, 837, 841, 849, 858, 866, 869, 870, 877, 882, 896, 937, 960, 995 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

EXAMPLE

a(3) = 27 is a term because A335592(27) = det(631, 563; 577, 619) = 65738 = 2*32869 and 32869 is prime.

MAPLE

count:= 0: R:= NULL:

L:= [-9, -7, -3, -1]:

for k from 1 while count < 100 do

  for i from 1 to 4 do

   for x from L[i]+10 by 10 do until isprime(x);

   L[i]:= x;

  od;

  v:= L[1]*L[4]-L[2]*L[3];

  if isprime(abs(v)/2) then count:= count+1; R:= R, k; fi

od:

R;

CROSSREFS

Cf. A335592, A336738.

Sequence in context: A302618 A171227 A061387 * A319970 A272834 A273573

Adjacent sequences:  A335590 A335591 A335592 * A335594 A335595 A335596

KEYWORD

nonn,base

AUTHOR

J. M. Bergot and Robert Israel, Jan 27 2021

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 23 17:37 EDT 2021. Contains 348215 sequences. (Running on oeis4.)