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.

A069529 Smallest multiple of n with digit sum = 10, or 0 if no such number exists, e.g. a(3k)= 0.

Original entry on oeis.org

19, 28, 0, 28, 55, 0, 28, 64, 0, 190, 55, 0, 91, 28, 0, 64, 136, 0, 19, 280, 0, 154, 46, 0, 325, 208, 0, 28, 145, 0, 217, 64, 0, 136, 280, 0, 37, 190, 0, 280, 82, 0, 172, 352, 0, 46, 235, 0, 343, 550, 0, 208, 424, 0, 55, 280, 0, 406, 118, 0, 244, 1054, 0, 64, 325, 0, 1072
Offset: 1

Views

Author

Amarnath Murthy, Apr 01 2002

Keywords

Comments

a(n) = 0 if n is a multiple of 3, 1111, 2849, 3367, 4649 or 5291.

Crossrefs

Programs

  • Maple
    unfinished:= true: V:= Vector(1000):
    V0:= select(t -> igcd(t, 3*4649) = 1 and t mod 1111 <> 0 and t mod 2849 <> 0 and t mod 3367 <> 0 and t mod 5291 <> 0, {$1..1000}):
    for i1 from 0 while unfinished do
      for i2 from 0 to i1 while unfinished do
        for i3 from 0 to i2 while unfinished do
          for i4 from 0 to i3 while unfinished do
            for i5 from 0 to i4 while unfinished do
              for i6 from 0 to i5 while unfinished do
                for i7 from 0 to i6 while unfinished do
                for i8 from 0 to i7 while unfinished do
                for i9 from 0 to i8 while unfinished do
                for i10 from 0 to i9 while unfinished do
                  v:= 10^i1 + 10^i2 + 10^i3 + 10^i4 + 10^i5 + 10^i6 + 10^i7 + 10^i8 + 10^i9 + 10^i10;
                  if convert(convert(v,base,10),`+`) <> 10 then next fi;
                  dv:= numtheory:-divisors(v);
                  for s in V0 intersect dv do
                    V[s]:= v;
                  od;
                  V0:= V0 minus dv;
                  unfinished:= evalb(V0 <> {});
    od od od od od od od od od od:
    convert(V,list); # Robert Israel, Feb 14 2024

Extensions

More terms from Sascha Kurz, Apr 08 2002