cp's OEIS Frontend

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.

Showing 1-2 of 2 results.

A378167 Differences between adjacent terms of A076467 that correspond to the locations described by A378166.

Original entry on oeis.org

8, 32, 343, 17576, 65610000, 11329982936, 26102469128, 315404039943, 152838610998696, 7327416190396311, 146668341275463896, 1097750613982270976
Offset: 1

Views

Author

Hugo Pfoertner, Nov 20 2024

Keywords

Comments

See A378166 for more information and examples.

Crossrefs

A378164 Smaller of consecutive terms b < c of A076467 such that the quality q=log(rad(c))/log(rad((c-b)*b*c)) of the abc-triple c-b,b,c with gcd(c-b,b,c)=1 sets a new record.

Original entry on oeis.org

1, 81, 1296, 2187, 1419857
Offset: 1

Views

Author

Hugo Pfoertner, Nov 18 2024

Keywords

Comments

If it exists, a(6)>5*10^27.

Examples

			           Pairs b,c of consecutive
           terms of A076467
  A378165
    c-b        b        c     Quality = log(rad(c))/log(rad((c-b)*b*c))
      7,       1,       8,    0.262649535...
     44,      81,     125,    0.277532712...
     35,    1296,    1331,    0.309605475...
     10,    2187,    2197,    0.429917243...
  23040, 1419857, 1442897,    0.431260235...
		

Crossrefs

A378165 gives the corresponding values of c-b.

Programs

  • PARI
    \\ Uses M. F. Hasler's A076467_vec from A076467
    a378164_5(upto) = {my(W=A076467_vec(upto), qw=0); for(k=2, #W, my(d=W[k]-W[k-1]); if(gcd([d,W[k],W[k-1]])==1, my(C=factor(W[k])[,1], B=factor(W[k-1])[,1], A=factor(d)[,1], P=vecprod(setunion(setunion(Set(B),Set(C)),Set(A))), q=log(vecprod(C))/log(P)); if(q>qw, print([d,W[k-1],W[k],q]); qw=q)))};
    a378164_5(10^16)
Showing 1-2 of 2 results.