login
A305162
Numbers k such that A127417(k) = 1.
0
1, 2, 12, 20, 24, 80, 84, 260, 264, 384, 512, 684, 960, 1304, 1784, 2760, 4800, 4824, 5312, 5984, 6032, 9920, 10340, 10440, 10512, 13272, 14964, 15720, 18704, 23232, 24464, 26084, 27440, 27720, 28224
OFFSET
1,2
COMMENTS
Numbers k such that for 2 <= m <= k-1, k is not congruent to -A127417(m) (mod m).
EXAMPLE
a(3)=12 is a term because A127417(12)=1; thus 12 is not congruent to -1 (mod 2), -2 (mod 3), -2 (mod 4), -2 (mod 5), -2 (mod 6), -3 (mod 7), -2 (mod 8), -2 (mod 9), -4 (mod 10) or -3 (mod 11).
MAPLE
N:= 20000: # to get terms up to N
A127417[1]:= 1:
Res:= NULL:
for n from 2 to N do
A127417[n]:= nops(select(t -> ((A127417[t]+n)/t)::integer, [$1..n-1]))
if A127417[n] = 1 then Res:= Res, n fi
od:
Res;
CROSSREFS
Cf. A127417.
Sequence in context: A277589 A069164 A067762 * A339709 A137311 A032407
KEYWORD
nonn
AUTHOR
Robert Israel, Aug 17 2018
STATUS
approved