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A101472
Numbers n such that the number n33 is prime.
4
2, 4, 7, 10, 14, 17, 19, 23, 26, 28, 34, 35, 37, 38, 41, 47, 49, 52, 53, 61, 67, 68, 73, 74, 79, 82, 89, 91, 94, 95, 97, 98, 101, 103, 104, 107, 116, 118, 119, 124, 130, 136, 139, 140, 145, 146, 152, 157, 160, 163, 164, 166, 170, 173, 181, 182, 184, 193, 194, 202
OFFSET
1,1
LINKS
Chris Caldwell The first 1,000 primes.
EXAMPLE
If n=2, then n33 = 233 (prime);
If n=34, then n33 = 3433 (prime);
If n=74, then n33 = 7433 (prime).
MATHEMATICA
fQ[n_] := PrimeQ[FromDigits[ Join[ IntegerDigits[n], {3, 3}]]]; Select[ Range[203], fQ[ # ] &] (* Robert G. Wilson v, Feb 04 2005 *)
Select[Range[250], PrimeQ[FromDigits[Flatten[{IntegerDigits[#], IntegerDigits[33]}]]] &] (* Vincenzo Librandi, Jul 31 2015 *)
Select[Range[210], PrimeQ[100#+33]&] (* Harvey P. Dale, Jul 04 2017 *)
PROG
(Magma) [n: n in [0..250] | IsPrime(Seqint(Intseq(33) cat Intseq(n)))]; // Vincenzo Librandi, Jul 31 2015
(PARI) is(n)=isprime(100*n+33) \\ Charles R Greathouse IV, May 22 2017
CROSSREFS
Sequence in context: A170894 A151986 A287522 * A273872 A087160 A336411
KEYWORD
nonn,base
AUTHOR
Parthasarathy Nambi, Jan 30 2005
EXTENSIONS
More terms from Robert G. Wilson v, Feb 04 2005
STATUS
approved