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liste_max:=100000; sieving:=proc (stelle, p) begin while (stelle<=liste_max) do erg:=liste[stelle]; while(erg mod p=0) do // Divison of the stored f(x) by the prime erg:=erg /p; end_while; liste[stelle]:=erg; stelle:=stelle+p; end_while; end_proc; // Calculation of the values of the polynom for x from 0 to liste_max for x from 0 to liste_max do p:=abs (a*x^2+b*x+c); while (p mod 2=0) p:=p/2; liste [x]:=p; end_for; for x from 0 to liste_max do p:=liste[x]; if (p>1) then // Printing the Primes print (x, p); // 1. Sieving sieving (x+p, p); t:=(-x-b/a) mod p;If you are interested in some better algorithms have a look at quadr_Sieb_x^2+1.php.
if t=0 then t:=p; end_if; // 2. Sieving sieving (t, p); end_if; end_for;
2. Mathematical background
Lemma: If p | f(x) then also p | f(x+p) and p | f(-x-b/a) a) p | f(x) <=> ax^2 + bx + c = 0 mod p p | f(x+p) <=> a(x+p)^2 + b(x+p) + c = 0 mod p <=> ax^2 + 2axp + ap^2 + bx + bp + c = 0 mod p <=> ax^2 + bx + c = 0 mod p Thus if p | f(x) then p | f(x+p) b) if b = 0 mod a p | f(x) <=> ax^2 + bx + c = 0 mod p p | f(-x-b/a) <=> a(-x-b/a)^2 + b(-x-b/a) + c = 0 mod p <=> ax^2 + 2bx + b^2/a - bx - b^2/a + c = 0 mod p <=> ax^2 + bx + c = 0 mod p Thus if p | f(x) then p | f(-x-b/a)3. Correctness of the algorithm
The proof for this polynom is similar to the proof for the polynom f(x)=x^2-4x+1. a) First terms for the polynom f(x) = x^2+36x-1013
f(0)=1013
f(1)=61
f(2)=937
f(3)=7
f(4)=853
f(5)=101
f(6)=761
f(7)=89
f(8)=661
f(9)=19
f(10)=79
f(11)=31
f(12)=23
f(13)=47
f(14)=313
f(15)=1
f(16)=181
f(17)=1
f(18)=41
f(19)=1
f(20)=107
f(21)=1
f(22)=263
f(23)=43
f(24)=1
f(25)=1
f(26)=599
f(27)=1
f(28)=1
f(29)=109
f(30)=967
f(31)=1
f(32)=1163
f(33)=1
f(34)=1367
f(35)=1
f(36)=1579
f(37)=211
f(38)=257
f(39)=239
f(40)=2027
f(41)=67
f(42)=73
f(43)=149
f(44)=1
f(45)=1
f(46)=1
f(47)=1
f(48)=3019
f(49)=197
f(50)=173
f(51)=1
f(52)=509
f(53)=463
f(54)=3847
f(55)=499
f(56)=4139
f(57)=1
f(58)=193
f(59)=1
f(60)=1
f(61)=613
f(62)=83
f(63)=653
f(64)=5387
f(65)=347
f(66)=1
f(67)=1
f(68)=1
f(69)=1
f(70)=1
f(71)=823
f(72)=6763
f(73)=1
f(74)=7127
f(75)=457
f(76)=7499
f(77)=1
f(78)=7879
f(79)=1009
f(80)=1181
f(81)=1
f(82)=8663
f(83)=277
f(84)=9067
f(85)=1
f(86)=9479
f(87)=1
f(88)=521
f(89)=1
f(90)=449
f(91)=659
f(92)=229
f(93)=1373
f(94)=1601
f(95)=1429
f(96)=131
f(97)=743
f(98)=12119
f(99)=1
b) Substitution of the polynom
The polynom f(x)=x^2+36x-1013 could be written as f(y)= y^2-1337 with x=y-18
c) Backsubstitution Beside by backsubstitution you get an estimation for the huge of the primes with p | f(x) and p < f(x) f'(y)>(2y-1) with with y=x+18
f'(x)>2x+35