A317400 Positive integers that have exactly ten representations of the form 1 + p1 * (1 + p2* ... * (1 + p_j)...), where [p1, ..., p_j] is a (possibly empty) list of distinct primes.

11306, 13289, 13693, 16402, 16446, 16491, 16699, 17031, 17113, 17116, 17263, 17576, 18412, 18602, 19825, 20023, 20411, 21022, 21256, 21676, 21936, 22271, 22543, 22716, 22764, 23038, 23233, 23332, 23353, 23580, 23599, 23886, 24036, 24053, 24064, 24531, 24646

Offset

1,1

Links

Alois P. Heinz, Table of n, a(n) for n = 1..20000

Formula

A317241(a(n)) = 10.

Maple

b:= proc(n, s) option remember; local p, r; if n=1 then 1 else r:=0;
      for p in numtheory[factorset](n-1) minus s while r<11
        do r:= r+b((n-1)/p, s union {p}) od; `if`(r<11, r, 11)
      fi
    end:
a:= proc(n) option remember; local k; for k from
     `if`(n=1, 1, 1+a(n-1)) while b(k, {})<>10 do od; k
    end:
seq(a(n), n=1..100);

Crossrefs

Column k=10 of A317390.

Cf. A317241.

Sequence in context: A177216 A112441 A104017 * A284814 A228627 A178581

Adjacent sequences: A317397 A317398 A317399 * A317401 A317402 A317403

Keyword

nonn

Author

Alois P. Heinz, Jul 27 2018

Status

approved