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A336738
Primes abs(A335592(k))/2 for k in A335593.
4
1399, 17939, 32869, 149759, 282349, 458929, 388099, 615389, 634169, 585619, 926179, 1053449, 1876339, 1336529, 2056829, 2156369, 2695249, 2653699, 2819779, 2501449, 1461709, 2176679, 3457969, 2549479, 3433819, 5299219, 4845499, 4774619, 7874749, 8796049, 9139469, 9029399, 7075759, 5156299
OFFSET
1,1
COMMENTS
All terms end in 9 (or 1, if there are any with A335592(k) < 0).
LINKS
FORMULA
a(n) = abs(A335592(A335593(n)))/2.
EXAMPLE
A335593(3) = 27, A335592(27) = det(631, 563; 577, 619) = 65738 = 2*32869
so a(3) = 32869.
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, abs(v)/2; fi
od:
R;
CROSSREFS
Sequence in context: A110844 A015990 A065214 * A271549 A203918 A178271
KEYWORD
nonn,base,look
AUTHOR
J. M. Bergot and Robert Israel, Jan 27 2021
STATUS
approved