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A343798
a(n) is the least k such that A343796(k) = n, or 0 if there is no such k.
2
1, 2, 4, 7, 25, 12, 16, 37, 24, 32, 33, 40, 67, 63, 48, 58, 78, 60, 81, 50, 102, 91, 114, 109, 110, 116, 117, 124, 130, 137, 120, 128, 152, 168, 190, 183, 184, 186, 215, 199, 206, 202, 259, 235, 208, 264, 261, 256, 269, 274, 281, 318, 272, 301, 316, 330, 329, 342, 327, 352, 326, 376, 346, 312
OFFSET
0,2
COMMENTS
a(n) is the least k such that there are exactly n distinct primes of the form A007504(k) mod p for the first k primes p.
LINKS
EXAMPLE
a(4) = 25 because A007504(25) = 1060 and there are 4 primes of the form 1060 mod p for the first 25 primes p: 2 = 1060 mod 23, 3 = 1060 mod 7, 7 = 1060 mod 13 and 23 = 1060 mod 61, and 25 is the first k that produces exactly 4 primes in this way.
MAPLE
N:= 100: # for a(0)..a(N)
V:= Array(0..N): count:= 0:
P:= {}: p:= 1: t:= 0:
for n from 1 while count < 100 do
p:= nextprime(p); P:= P union {p}; t:= t+p;
v:= nops(select(isprime, map(s -> t mod s, P)));
if v <= N and V[v] = 0 then
V[v]:= n; count:= count+1;
fi
od:
convert(V, list);
CROSSREFS
Sequence in context: A359095 A036440 A103001 * A222987 A222907 A179386
KEYWORD
nonn
AUTHOR
J. M. Bergot and Robert Israel, Apr 29 2021
STATUS
approved