A139603 Duplicate of A141183.
2, 7, 11, 19, 43, 79, 83, 107, 127, 131, 139, 151, 167, 211, 227, 239, 263, 271, 283, 307, 347, 359, 431, 439, 479, 491, 503, 523, 547, 563, 571, 607, 659, 739, 743, 787, 811, 827, 887, 919, 967
Offset: 1
This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
19 is a member because we can write 19=4*2^2+4*2*1-5*1^2 (or 19=4*1^2+12*1*1+3*1^2).
[3] cat [ p: p in PrimesUpTo(3000) | p mod 24 in {19 } ]; // Vincenzo Librandi, Jul 24 2012
QuadPrimes2[3, 0, 16, 10000] (* see A106856 *)
list(lim)=my(v=List(),w,t); for(x=1, sqrtint(lim\3), w=3*x^2; for(y=0, sqrtint((lim-w)\16), if(isprime(t=w+16*y^2), listput(v,t)))); Set(v) \\ Charles R Greathouse IV, Feb 09 2017
a(3)=53 because we can write 53=5^2+6*5*1-2*1^2 (or 53=5*1^2+8*1*4+4^2)
Select[Prime[Range[250]], MatchQ[Mod[#, 44], Alternatives[1, 5, 9, 25, 37]] &] (* Jean-François Alcover, Oct 28 2016 *)
isA141182(p) = p%4==1 & issquare(Mod(p,11)) \\ M. F. Hasler, Mar 20 2011
a(2) = 3 because we can write 3 = 4*1^2 + 3*1*1 - 4*1^2.
a(1) = 3 because we can write 3 = 3*1^2 + 5*1*0 - 5*0^2 (or 3 = 7*0^2 + 13*0*1 + 3*1^2).
a(1) = 2 because we can write 2 = 4*1^2 + 3*1*1 - 5*1^2.
Comments