A095787 - OEIS

A095787

Numbers n such that A095163(n) is different from A033677(n).

20, 30, 42, 48, 54, 56, 72, 80, 88, 90, 96, 99, 104, 108, 110, 117, 120, 126, 130, 132, 140, 143, 150, 154, 156, 160, 168, 180, 182, 192, 195, 204, 208, 210, 216, 221, 224, 228, 234, 238, 240, 252, 255, 264, 266, 270, 272, 280, 285, 288, 294, 300, 304, 306

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OFFSET

1,1

COMMENTS

A095163(n) <= A033677(n).

LINKS

Table of n, a(n) for n=1..54.

EXAMPLE

A095163(54) = 6, A033677(54) = 9, so 54 is in the sequence.

For n = 12 we have divisors 1, 2, 3, 4, 6, 12; 1 occurs earlier once, 2 occurs earlier twice, 3 occurs earlier 3 times, but 4 occurs earlier only once, hence a(12) = 4.

PROG

(PARI) {m=310; v=vector(m); for(n=1, m, d=divisors(n); j=1; while(v[d[j]]>=d[j], j++); x=d[j]; v[d[j]]=v[d[j]]+1; r=sqrt(n); j=1; while(d[j]<r, j++); y=d[j]; if(x!=y, print1(n, ", ")))}

(PARI) {m=80; v=vector(m); for(n=1, m, d=divisors(n); j=1; while(v[d[j]]>=d[j], j++); print1(d[j], ", "); v[d[j]]=v[d[j]]+1)}

CROSSREFS

Cf. A095163, A033677.

Sequence in context: A166730 A109944 A108030 * A198471 A120145 A104048

Adjacent sequences: A095784 A095785 A095786 * A095788 A095789 A095790

KEYWORD

nonn

AUTHOR

Klaus Brockhaus, Jun 05 2004

STATUS

approved