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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
OFFSET
1,1
COMMENTS
If n is prime, a(n) = n. - Robert Israel, Oct 27 2016
LINKS
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: A177764 A339402 A027498 * A359354 A006560 A088251
KEYWORD
easy,base,nonn
AUTHOR
Jason Earls, Jun 15 2004
STATUS
approved