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A352605 Primes p such that the floor of the area of a triangle with sides p-1, p and p+1 is prime. 1
3, 41, 97, 127, 163, 179, 239, 277, 367, 439, 443, 541, 569, 571, 577, 593, 677, 719, 809, 877, 1013, 1087, 1201, 1259, 1439, 1553, 1601, 1609, 1721, 1871, 1879, 1889, 2063, 2143, 2179, 2273, 2281, 2689, 2803, 2819, 2887, 3137, 3313, 3511, 3527, 3637, 3797, 3847, 3911, 4049, 4091, 4441, 4933 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Primes p such that floor(p*sqrt(3*(p^2-4))/4) is prime.

LINKS

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

EXAMPLE

a(3) = 97 is a term because 97 is prime, the area of a triangle with sides 96, 97 and 98 is 4073.35..., and 4073 is prime.

MAPLE

filter:= p -> isprime(floor(p/4*sqrt(3*(p^2-4)))):

select(filter, [seq(ithprime(i), i=1..10000)]);

CROSSREFS

Cf. A096378.

Sequence in context: A157009 A100765 A092168 * A229080 A289270 A262555

Adjacent sequences:  A352602 A352603 A352604 * A352606 A352607 A352608

KEYWORD

nonn

AUTHOR

J. M. Bergot and Robert Israel, Mar 22 2022

STATUS

approved

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Last modified August 8 15:35 EDT 2022. Contains 356009 sequences. (Running on oeis4.)