The On-Line Encyclopedia of Integer Sequences (OEIS)

A272376 revision #11

A272376

Twin primes that are the sum of three positive cubes.

2267, 2269, 3527, 3529, 10331, 10333, 14867, 14869, 17207, 17209, 18521, 18523, 18917, 18919, 20231, 20233, 20357, 20359, 25577, 25579, 27791, 27793, 28547, 28549, 31247, 31249, 35279, 35281, 36899, 36901, 40697, 40699, 44279, 44281, 48779, 48781, 51479, 51481

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

LINKS

Table of n, a(n) for n=1..38.

EXAMPLE

3527 and 3529 since 3527=3^3+5^3+15^3 and 3529=1^3+11^3+13^3.

MATHEMATICA

cu[n_] := {}!=Quiet@ IntegerPartitions[n, {3}, Range[n^(1/3)]^3, 1]; Flatten@ Rest@ Reap@ Do[If[ PrimeQ[p+2] && cu[p] && cu[p+2], Sow[{p, p+2}]], {p, Prime@ Range@ 10000}] (* Giovanni Resta, Apr 28 2016 *)

PROG

(PARI) list(lim)=my(v=List(), k, t); lim\=1; for(x=1, sqrtnint(lim-2, 3), for(y=1, min(sqrtnint(lim-x^3-1, 3), x), k=x^3+y^3; for(z=1, min(sqrtnint(lim-k, 3), y), if(isprime(t=k+z^3) && (isprime(t-2) || isprime(t+2)), listput(v, t))))); Set(v) \\ Charles R Greathouse IV, Apr 29 2016

CROSSREFS

Cf. A001097, A007490.

Sequence in context: A251509 A263972 A263963 * A288883 A206212 A154673

Adjacent sequences: A272373 A272374 A272375 * A272377 A272378 A272379

KEYWORD

nonn

AUTHOR

Carmine Suriano, Apr 28 2016

STATUS

editing