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A228761
Primes of the concatenated form 149x149 for some number x.
1
1496149, 1497149, 1499149, 14915149, 14924149, 14925149, 14928149, 14931149, 14942149, 14945149, 14951149, 14976149, 14985149, 14991149, 149124149, 149127149, 149132149, 149135149, 149150149, 149153149, 149159149, 149162149, 149171149, 149175149, 149187149, 149192149
OFFSET
1,1
COMMENTS
Sequence is infinite. - Charles R Greathouse IV, Sep 03 2013
LINKS
FORMULA
Primes of the form parse(cat(149,x,149)).
EXAMPLE
a(1)= 1496149 is a term in the sequence as it is a prime of the form abcxabc: abc are square digits 1,4 and 9 in order.
MAPLE
with(StringTools): KD:= proc() local a, b; a:= 149; b:=parse(cat(a, x, a)); if isprime(b) then RETURN(b): fi; end: seq(KD(), x=1..1000);
MATHEMATICA
With[{c={1, 4, 9}}, Select[Table[FromDigits[Join[c, IntegerDigits[n], c]], {n, 200}], PrimeQ]](* Harvey P. Dale, Jan 14 2015 *)
PROG
(PARI) for(x=1, 1e3, if(ispseudoprime(t=eval(Str(149, x, 149))), print1(t", "))) \\ Charles R Greathouse IV, Sep 03 2013
CROSSREFS
Sequence in context: A128837 A297881 A335289 * A206060 A251973 A236499
KEYWORD
nonn,base,less
AUTHOR
K. D. Bajpai, Sep 03 2013
STATUS
approved