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A341252
a(n) is the least k such that there are exactly n pairs of consecutive primes (p,q) such that (2*k-q,2*k-p) are consecutive primes.
1
1, 4, 5, 9, 33, 12, 24, 39, 51, 30, 63, 72, 84, 45, 57, 102, 123, 60, 297, 351, 162, 120, 252, 231, 519, 150, 285, 195, 345, 105, 360, 165, 255, 483, 510, 462, 1182, 552, 210, 1158, 330, 315, 1023, 1197, 525, 570, 690, 675, 1353, 858, 750, 645, 585, 987, 1533, 420, 900, 825, 1110, 660, 630, 960
OFFSET
0,2
COMMENTS
a(n) is the least k such that A341237(k) = n.
LINKS
EXAMPLE
a(3) = 9 as there are 3 pairs (p,q) = (5,7), (7,11), (11,13) of consecutive primes such that (18-q,18-p) = (11,13), (7,11), (5,7) are pairs of consecutive primes, and 9 is the least number for which there are 3 such pairs.
MAPLE
f:= proc(n) local p, q, count;
q:= 2: count:= 0:
while q < 2*n -2 do
p:= q; q:= nextprime(q);
if isprime(2*n-p) and prevprime(2*n-p)=2*n-q then count:= count+1 fi;
od;
count
end proc:
V:= Array(0..100): count:= 0:
for n from 1 while count < 101 do
v:= f(n);
if v <= 100 and V[v] = 0 then count:= count+1; V[v]:= n fi
od:
convert(V, list);
CROSSREFS
Sequence in context: A352509 A222543 A042221 * A041151 A279919 A041467
KEYWORD
nonn
AUTHOR
J. M. Bergot and Robert Israel, Feb 07 2021
STATUS
approved