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A094877 Primes that are reached in A094830. 3
2, 2, 3, 199, 5, 107, 7, 547, 263, 11, 11, 17, 13, 31, 41, 53, 17, 83, 19, 199, 643, 563, 23, 199, 547, 643, 1301, 227, 29, 563, 31, 643, 439, 59, 643, 199, 37, 199, 563, 269, 41, 107, 43, 199, 643, 643, 47, 197, 199, 149, 439, 199, 53, 547, 131, 269, 131, 227, 59 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

If n is prime, a(n) = n. - Robert Israel, Oct 27 2016

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

MAPLE

f:= proc(n) local x, t;

  x:= n;

  do

   if isprime(x) then return x fi;

   x:= x + add(t^2, t = convert(x, base, 10))

  od;

end proc:

map(f, [$1..100]); # Robert Israel, Oct 27 2016

MATHEMATICA

p2[n_]:=NestWhile[#+Total[IntegerDigits[#]^2]&, n, !PrimeQ[#]&]; Array[p2, 60] (* Harvey P. Dale, Dec 03 2011 *)

CROSSREFS

Cf. A094830.

Sequence in context: A246718 A177764 A027498 * A006560 A088251 A229627

Adjacent sequences:  A094874 A094875 A094876 * A094878 A094879 A094880

KEYWORD

easy,base,nonn

AUTHOR

Jason Earls, Jun 15 2004

STATUS

approved

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Last modified January 22 12:13 EST 2019. Contains 319363 sequences. (Running on oeis4.)