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A346653
Numbers p that are the first of three consecutive primes p,q,r such that p*q*r-(p+q+r) and p*q*r+(p+q+r) are both in A001043.
1
3, 1579, 3967, 14323, 30763, 32189, 41389, 61471, 70117, 74051, 74707, 79691, 95239, 154157, 157181, 157433, 169003, 184321, 215063, 237563, 265271, 300877, 303217, 320741, 326119, 366713, 382241, 392531, 408689, 544723, 572749, 584099, 587219, 615103, 639487, 653561, 674231, 687151, 698483
OFFSET
1,1
COMMENTS
Numbers p that are the first of three consecutive primes p,q,r such that p*q*r-(p+q+r) is the sum of two consecutive primes and p*q*r+(p+q+r) is the sum of two consecutive primes.
LINKS
EXAMPLE
a(3) = 3967 is a term because 3967, 3989, 4001 are consecutive primes with
3967*3989*4001-(3967+3989+4001) = 63313264406 = 31656632197+31656632209,
3967*3989*4001+(3967+3989+4001) = 63313288320 = 31656644153+31656644167,
31656632197 and 31656632209 are consecutive primes
and 31656644153 and 31656644167 are consecutive primes.
MAPLE
q:= 2: r:= 3:
R:= NULL: count:= 0:
while count < 40 do
p:= q; q:= r; r:= nextprime(r);
s:= p+q+r;
v:= p*q*r+s;
t:= prevprime(v/2);
if nextprime(t)+t <> v then next fi;
v:= v-2*s;
t:= prevprime(v/2);
if nextprime(t)+t = v then
count:= count+1;
R:= R, p;
fi
od:
R;
CROSSREFS
Cf. A001043.
Sequence in context: A118050 A246637 A302132 * A258720 A262652 A262500
KEYWORD
nonn
AUTHOR
J. M. Bergot and Robert Israel, Jul 26 2021
STATUS
approved