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!)
A167412 Primes p such that sum of (digits^2) + 1 is prime. 2
2, 11, 13, 19, 31, 37, 59, 73, 79, 97, 101, 103, 109, 163, 181, 211, 233, 251, 257, 277, 307, 349, 383, 439, 499, 509, 521, 541, 563, 587, 613, 631, 653, 709, 727, 769, 787, 811, 857, 877, 907, 929, 967, 1009, 1021, 1063, 1117, 1151, 1153, 1171, 1201, 1223 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

11 is a term because 1^2 + 1^2 + 1 = 3 (prime);

163 is a term because 1^2 + 6^2 + 3^2 + 1 = 47;

277 is a term because 2^2 + 7^2 + 7^2 + 1 = 103.

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1300

MAPLE

A003132 := proc(n) local d; add(d^2, d=convert(n, base, 10)) ; end proc: A167412 := proc(n) local p; if n = 1 then 2; else p := nextprime(procname(n-1)) ; while not isprime(A003132(p)+1) do p := nextprime(p) ; end do ; return p end if ; end proc: seq(A167412(n), n=1..80) ; # R. J. Mathar, Nov 04 2009

MATHEMATICA

Select[Prime[Range[2000]], PrimeQ[Total[IntegerDigits[#]^2] + 1]&] (* Vincenzo Librandi, Sep 25 2014 *)

CROSSREFS

Cf. A167414.

Sequence in context: A207039 A095743 A106984 * A166561 A179462 A207192

Adjacent sequences:  A167409 A167410 A167411 * A167413 A167414 A167415

KEYWORD

nonn,base

AUTHOR

Vincenzo Librandi, Nov 03 2009

EXTENSIONS

2, 211, 233 inserted and more terms after 653 added by R. J. Mathar, Nov 04 2009

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 February 25 11:46 EST 2021. Contains 341606 sequences. (Running on oeis4.)