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!)
A188698 Numbers k such that 1+k, 1+k^2, 1+k^4 and 1+k^16 are all prime. 0
1, 2, 690, 33190, 57106, 77140, 135606, 258990, 303430, 331140, 337536, 359230, 375646, 455526, 458326, 493396, 548226, 550540, 585106, 602056, 659250, 680830, 742306, 800406, 827680, 870240, 918340, 925390, 968320, 1203100, 1273890, 1455526, 1497576, 1605016 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Subsequence of A070325, which itself is a subsequence of A070689, which itself is a subsequence of A006093.

LINKS

Table of n, a(n) for n=1..34.

EXAMPLE

a(3) = 690 = A070689(32) = A070325(11) = A006093(125).

PROG

(MAGMA) [n: n in [0..7000000]| IsPrime(1+n) and IsPrime(1+n^2) and IsPrime(1+n^4) and IsPrime(1+n^16)]; // Vincenzo Librandi, Apr 11 2011

CROSSREFS

Sequence in context: A079195 A120123 A140014 * A209364 A106301 A127623

Adjacent sequences:  A188695 A188696 A188697 * A188699 A188700 A188701

KEYWORD

nonn

AUTHOR

Zak Seidov, Apr 09 2011

EXTENSIONS

a(1) = 1 prepended by Vincenzo Librandi, Apr 11 2011

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 October 29 04:54 EDT 2020. Contains 338066 sequences. (Running on oeis4.)