login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A239941 Primes p which are floor of Root-mean-cube (RMC) of prime(n), prime(n+1) and prime(n+2). 1
7, 53, 89, 223, 257, 1097, 6823, 10181, 12149, 14783, 15527, 20063, 22027, 29917, 30539, 40519, 42491, 43261, 50543, 51511, 57727, 65063, 68639, 72103, 97453, 99391, 100693, 108463, 108893, 110281, 111581, 113363, 116719, 149623, 153407, 154211, 155821, 193057 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

K. D. Bajpai, Table of n, a(n) for n = 1..1745

EXAMPLE

11, 13 and 17 are consecutive primes: sqrt(( 11^3 + 13^3 + 17^3)/3) = 53.04400689: floor(53.04400689) = 53, which is prime and appears in the sequence.

31, 37 and 41 are consecutive primes: sqrt(( 31^3 + 37^3 + 41^3)/3) = 223.1329947: floor(223.1329947) = 223, which is prime and appears in the sequence.

MAPLE

KD := proc() local a, b, d, e; a:=ithprime(n); b:=ithprime(n+1); d:=ithprime(n+2); e:=floor(evalf(sqrt(((a^3+b^3+d^3)/3)))); if isprime(e) then  RETURN (e); fi; end: seq(KD(), n=1..1000);

CROSSREFS

Cf. A000040, A075471, A088165.

Sequence in context: A224501 A241487 A236688 * A253123 A141911 A200766

Adjacent sequences:  A239938 A239939 A239940 * A239942 A239943 A239944

KEYWORD

nonn

AUTHOR

K. D. Bajpai, Apr 03 2014

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified August 11 05:42 EDT 2020. Contains 336422 sequences. (Running on oeis4.)