A274679 Numbers m such that 7*10^m + 33 is prime.

1, 2, 6, 10, 17, 29, 53, 107, 133, 596, 852, 1068, 1186, 1356, 1673, 1987, 3170, 3312, 5819, 6655, 19267, 20009, 29302, 72614, 170348, 178566

Offset

1,2

Links

Table of n, a(n) for n=1..26.

Makoto Kamada, Search for 70w33.

Example

2 is in this sequence because 7*10^2 + 33 = 733 is prime.
4 is not in the sequence because 7*10^4 + 33 = 70033 = 59 * 1187.
Initial terms and associated primes:
a(1) = 1: 103;
a(2) = 2: 733;
a(3) = 6: 7000033;
a(4) = 10: 70000000033, etc.

Mathematica

Select[Range[0, 3000], PrimeQ[7 10^# + 33] &]

Prog

(Magma) [n: n in [1..500] | IsPrime(7*10^n+33)];
(PARI) lista(nn) = for(n=1, nn, if(ispseudoprime(7*10^n+33), print1(n, ", "))); \\ Altug Alkan, Jul 05 2016

Crossrefs

Cf. similar sequences listed in A274676.

Sequence in context: A190695 A238377 A180739 * A229218 A255174 A140777

Adjacent sequences: A274676 A274677 A274678 * A274680 A274681 A274682

Keyword

nonn,more,changed

Author

Vincenzo Librandi, Jul 04 2016

Extensions

a(19)-a(20) from Michael S. Branicky, Aug 16 2021

a(21)-a(26) from Kamada data by Tyler Busby, Apr 14 2024

Status

approved