A258968 a(n) is the least positive integer x with A054973(x) = n and A258913(x) < x.

2, 3, 124, 10714158

Offset: 0

Author

Jeppe Stig Nielsen, Jun 15 2015

Keywords

• nonn
• more

Comments

Is a(n) well-defined for all n?

For n > 1, a(n) belongs to sequence A258931.

The terms a(k), for 4 <= k <= 100, if they exist, are larger than 3*10^10. - Giovanni Resta, Jun 15 2015

Examples

			For n=2, sigma(x)=124 for x=48 and 75, and 48+75 = 123 < 124.
For n=3, sigma(x)=10714158 for x=3031200, 3417300, and 3987450; and their sum is 10435950 (<10714158).
		

Crossrefs

Cf. A054973, A258913, A258931, A007368, A258914.

Programs

PARI

a(n)=x=0;while(x++,u=List();for(i=1,x,if(sigma(i)==x,listput(u,i)));if(#u==n&vecsum(Vec(u))