OFFSET
1,3
LINKS
Andrew Howroyd, Table of n, a(n) for n = 1..10000
MATHEMATICA
T[n_] := n*(n + 1)/2; f[n_] := Block[{dc = DigitCount[n], s}, s = Select[dc, Positive]; Min @@ s == Max @@ s]; Select[Array[T, 70, 0], f] (* Ray Chandler, May 11 2007 *)
PROG
(PARI) \\ here isok(k) tests if each digit k has equal frequency.
isok(k)={my(f=vector(10)); foreach(digits(k), t, f[1+t]++); my(c=vecmax(f)); 0==#select(t->t>0&&t<c, f)}
lista(n)={my(L=List(), k=0); while(#L<n, my(t=k*(k+1)/2); if(isok(t), listput(L, t)); k++); Vec(L)} \\ Andrew Howroyd, Sep 21 2024
CROSSREFS
KEYWORD
base,easy,nonn
AUTHOR
Amarnath Murthy, Nov 24 2002
EXTENSIONS
Offset changed by Andrew Howroyd, Sep 21 2024
STATUS
approved