A051735 Binomial coefficients C(n,k) such that C(n,k)-1 and C(n,k)+1 are twin primes and 2<=k<=floor(n/2).

6, 462, 1877405874732108, 38650751381832, 10000119226331142599460, 51913710643776705684835560, 42552226353687619569660660, 1656627950725900171898183550, 315676747963758694790502389846048040560005901701920, 3571770735028382091998706667681023581492775768

Offset

0,1

Comments

Sequence is ordered by size of n not size of C(n,k). Link gives list of all values up to n=1352.

Links

Table of n, a(n) for n=0..9.

More terms

Example

C(11,5)=462 is a member of the sequence because 461 and 463 are twin primes.

Mathematica

Select[Flatten[Table[Binomial[n, k], {n, 200}, {k, 2, Floor[n/2]}]], AllTrue[ #+ {1, -1}, PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Dec 10 2015 *)

Crossrefs

See A051770 for values of n, A051771 for values of k.

Sequence in context: A338943 A232593 A267082 * A024084 A332146 A132590

Adjacent sequences: A051732 A051733 A051734 * A051736 A051737 A051738

Keyword

nonn

Author

Joe DeMaio (jdemaio(AT)kennesaw.edu), Dec 06 1999

Extensions

More terms from Harvey P. Dale, Dec 10 2015

Status

approved