A384584 Numbers k such that A383844(k) = 2.

4, 46, 62, 119, 145, 180, 200, 247, 305, 522, 707, 900, 1235, 1504, 1532, 1540, 2396, 3140, 4181, 4231, 6419, 9066, 9885, 14292, 17914, 22696, 33924, 35933, 38951, 80602

Offset

1,1

Comments

Numbers k such that there are exactly two m such that Sum_{i=1..t} m mod prime(i) for prime(t) <= m < prime(t+1) is equal to k (see A024934).

A383844(s) <= 3 for s <= 82000, with A383844(s) = 3 only for s = 0, 1, 8, 37, 781.

Links

Table of n, a(n) for n=1..30.

Example

4 is a term since 7 and 10 are the only numbers r such that A024934(r) = 4.
46 is a term since 29 and 30 are the only numbers r such that A024934(r) = 46.
9066 is a term since 552 and 566 are the only numbers r such that A024934(r) = 9066.

Prog

(PARI) isok(n) = (count(n) = my(f, S=[], b); (f(m) = my(r=0); forprime(p=2, m, r+=m%p); return(r)); if(n<=21, b=26, b=n); for(k=0, b, if(f(k)==n, S=concat(S, k))); return(#S)); if(count(n)==2, return(1), return(0))

Crossrefs

Cf. A024934, A383844.

Sequence in context: A389138 A374591 A134110 * A176312 A309450 A119046

Adjacent sequences: A384581 A384582 A384583 * A384585 A384586 A384587

Keyword

nonn,more

Author

Miles Englezou, Jun 04 2025

Status

approved