The Shadow Polynomial

P(x) = (x-1)(x-2)(x-3)(x-5)

This polynomial has roots at {1, 2, 3, 5}. Its coefficients are 11, 41, 61, and 30. Evaluate P at integers from 6 to 13: every result factors entirely into primes from {2, 3, 5, 7, 11}. The factorizations connect to E8, the Fano plane, and factorials.

Evaluations at Integer Points

Shadow Evaluation (PROVED)
P(x) = x^4 - 11x^3 + 41x^2 - 61x + 30. Every evaluation at integers 6 through 13 is 11-smooth (factors only into {2,3,5,7,11}).
xP(x)FactorizationConnection
0302 * 3 * 5Coxeter number of E8
6604 * 3 * 5lambda of Z/2,310
724016 * 3 * 5|roots(E8)|
86302 * 9 * 5 * 7
9134464 * 3 * 78 * |PSL(2,7)|
1025208 * 9 * 5 * 7lcm(1..9)
11432032 * 27 * 5
1269302 * 9 * 5 * 7 * 113 * primorial(11)
131056064 * 3 * 5 * 11All 5 primes present

Note: 5 is absent from P(9) = 1344. This is the only evaluation in the range where one of the five primes drops out. At x = 9, the factor (9-5) = 4 contributes only powers of 2.

P(7) = 240 = E8 Root Count

The E8 root system has 240 roots. E8 has rank 8 and Coxeter number 30. Roots = rank * Coxeter = 8 * 30 = 240.

P(7) = 240
= 6 * 5 * 4 * 2
The four factors are (7-1)(7-2)(7-3)(7-5). Product = |roots(E8)|.
P(7)/P(0) = 8
= rank(E8)
P(0) = 30 = Coxeter number. P(7) = 30 * 8. The ratio is the rank.
P(17) = 40,320
= 8!
P at 17 is the factorial of 8. Also: 40,320 = 240 * 168 = |roots(E8)| * |PSL(2,7)|.

The Mirror Identity

Mirror Identity (PROVED)
P(-1) = P(11)/P(0) = 4320/30 = 144. Proof: P(-1) = (-2)(-3)(-4)(-6) = 144. P(11) = 10*9*8*6 = 4320. P(0) = 1*2*3*5 = 30. Ratio = 144. The polynomial at -1 equals the ratio of its value at 11 to its value at 0.

CRT Root Anatomy

CRT Root Theorem (PROVED)
P(x) has 5 roots mod 8 and mod 9 (extra root: -1), but exactly 4 roots modulo 25, 49, 11, 13, and 17. Root count sum across all 7 channels = 30 = P(0). Non-root sum = 102. Discriminant = 2304 = 48^2.

Why 5 roots mod 8 and 9? Because P(-1) = 144 is divisible by 8 and 9 but not by 25 or 49. So -1 is an extra root only in the mod-8 and mod-9 channels.

ChannelModulusRootsNon-roots
mod 885 (incl. -1)3
mod 995 (incl. -1)4
mod 2525421
mod 4949445
mod 111147
mod 131349
mod 1717413
Root sum
5+5+4+4+4+4+4 = 30
= P(0). The root count across all channels equals the polynomial evaluated at zero.
Non-root sum
3+4+21+45+7+9+13 = 102
= 2*3*17. The complement is governed by 17, the ring-closing prime.
Discriminant
disc(P) = 2304 = 48^2
= 2^8 * 3^2. Only 2 and 3 (the first two chain primes) appear.

The Ratio Staircase

Ratio Staircase (PROVED)
P(p)/P(0) = 2^k * cofactor for each non-root prime p. Cofactors {1, 9, 11, 21} sum to 42. Powers of 2 sum to 8+16+32+64 = 120 = 5!.
pP(p)/30Power of 2Cofactor
782^3 = 81
111442^4 = 169
133522^5 = 3211
1713442^6 = 6421
Cofactor sum
1 + 9 + 11 + 21 = 42
= 2*3*7. The cofactors at the four non-root primes sum to 42.
Power-of-2 sum
8+16+32+64 = 120
= 5!. The 2-powers in the staircase sum to the factorial of 5.
P(17)/P(7)
40320/240 = 168
= |PSL(2,7)| = |Aut(Fano)|. The ratio of P at 17 to P at 7 is the Fano plane symmetry group.

Explore: P(x) Evaluator

Enter any integer x. Compute P(x) = (x-1)(x-2)(x-3)(x-5). For x from 6 to 13, every result factors into {2, 3, 5, 7, 11} only.

Evaluate P(x) at:

Try: 7 (240 = E8 roots), 9 (1344 = 8*168), 10 (2520 = lcm(1..9)), 13 (10560), 16 (30030 = primorial(13)), 17 (40320 = 8!).

Contrast

PolynomialRoots at {1,2,3,5}. Four small primes, nothing special about the polynomial itselfCoefficients are 11, 41, 61, 30. Every evaluation at integers 6 through 13 is 11-smooth. Factorizations hit E8 and PSL(2,7).P(7) = 240A product of four consecutive-ish differences= |roots(E8)| = 8 * 30 = rank * Coxeter. P(7)/P(0) = 8 = rank.P(9) = 1344= 2^6 * 3 * 7. A factorization= 8 * 168 = 8 * |PSL(2,7)|. The only evaluation where 5 drops out.P(17) = 8!A factorial that happens to match= 240 * 168 = |roots(E8)| * |PSL(2,7)|. Two algebraic structures whose product is 8!.Ratios P(p)/30Grow with p, no pattern expectedPower-of-2 staircase: cofactors {1, 9, 11, 21} sum to 42. 2-powers sum to 120 = 5!.

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