login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A084163
Primes which are -1 mod m, where m is the index of the prime in sequence A002313 (Real primes with corresponding complex primes). The index m can be found in A084164 Primes which are 1 mod m can be found in sequence A084165.
3
29, 41, 197, 229, 269, 2617, 2729, 2897, 4649, 37201, 37277, 169553, 170081, 170873, 282577, 9491309, 9493889, 15614761, 69955373, 69955577, 115195429, 115196129, 312316481, 513773717, 846651233, 3778288373, 3778289381, 3778290641
OFFSET
1,1
COMMENTS
Real primes 2,5,13,17,29,37,... have a unique representation as sum of two squares. Values larger 2 are the primes p with p = 1 mod 4. This is sequence A002313. If p = x^2 + y^2, the corresponding complex prime is x+y*i. First complex prime is 1+i with 2 as corresponding real prime, according to reference, page 1-2.
REFERENCES
Handbook of First Complex Prime Numbers, Part1+2 Ervand Kogbetliantz and Alice Krikorian, Gordon and Breach, 1971. The list in Part 2 contains an error: on page 919, column 2, number 5 is printed twice, so the indices after that number are wrong.
EXAMPLE
197 is the 22nd prime in sequence A002313, 22*9 = 198, so 197 = -1 mod 22.
CROSSREFS
KEYWORD
nonn
AUTHOR
Sven Simon, May 17 2003
STATUS
approved