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A103408
Numbers n such that n2101 is prime.
2
1, 4, 7, 10, 18, 24, 25, 28, 31, 34, 39, 42, 48, 51, 63, 70, 73, 76, 79, 81, 85, 93, 94, 100, 126, 139, 148, 150, 156, 157, 160, 163, 168, 174, 177, 184, 186, 199, 202, 207, 219, 232, 234, 235, 237, 265, 268, 277, 300, 301, 307, 309, 315, 316, 321, 322, 328, 343, 354, 358, 364, 366
OFFSET
1,2
LINKS
EXAMPLE
If n=1, then n2101 = 12101 (prime).
If n=31, then n2101 = 312101 (prime).
If n=63, then n2101 = 632101 (prime).
MATHEMATICA
Select[Range[400], PrimeQ[10000#+2101]&] (* Harvey P. Dale, Jul 20 2015 *)
PROG
(Magma) [ n: n in [1..700] | IsPrime(Seqint([1, 0, 1, 2] cat Intseq(n))) ]; // Vincenzo Librandi, Feb 03 2011
(PARI) is(n)=isprime(10000*n+2101) \\ Charles R Greathouse IV, Jun 06 2017
CROSSREFS
Sequence in context: A071415 A310718 A310719 * A208717 A208773 A088408
KEYWORD
base,nonn,easy
AUTHOR
Parthasarathy Nambi, Mar 20 2005
STATUS
approved