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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^2-188x+197
f(0)=197
f(1)=5
f(2)=7
f(3)=179
f(4)=11
f(5)=359
f(6)=1
f(7)=107
f(8)=113
f(9)=101
f(10)=1583
f(11)=1
f(12)=383
f(13)=1039
f(14)=2239
f(15)=109
f(16)=73
f(17)=271
f(18)=409
f(19)=137
f(20)=3163
f(21)=331
f(22)=691
f(23)=257
f(24)=3739
f(25)=277
f(26)=1
f(27)=83
f(28)=4283
f(29)=2207
f(30)=59
f(31)=467
f(32)=1
f(33)=2459
f(34)=5039
f(35)=2579
f(36)=211
f(37)=1
f(38)=5503
f(39)=401
f(40)=97
f(41)=53
f(42)=1187
f(43)=3019
f(44)=877
f(45)=3119
f(46)=181
f(47)=643
f(48)=593
f(49)=3307
f(50)=6703
f(51)=1
f(52)=1
f(53)=71
f(54)=7039
f(55)=3559
f(56)=1439
f(57)=727
f(58)=1049
f(59)=337
f(60)=1069
f(61)=151
f(62)=1523
f(63)=349
f(64)=1
f(65)=557
f(66)=1571
f(67)=1
f(68)=7963
f(69)=4007
f(70)=733
f(71)=811
f(72)=233
f(73)=4099
f(74)=1
f(75)=4139
f(76)=1663
f(77)=167
f(78)=1
f(79)=601
f(80)=8443
f(81)=1
f(82)=1699
f(83)=4259
f(84)=8539
f(85)=389
f(86)=1
f(87)=859
f(88)=1229
f(89)=1
f(90)=8623
f(91)=863
f(92)=157
f(93)=617
f(94)=163
f(95)=1
f(96)=1
f(97)=1
f(98)=1
f(99)=1
b) Substitution of the polynom
The polynom f(x)=x^2-188x+197 could be written as f(y)= y^2-8639 with x=y+94
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-94
f'(x)>2x-189 with x > 93