A343412 Numbers k such that k + A000203(k) + A001414(A000203(k)) is prime.

1, 3, 8, 14, 17, 18, 28, 31, 42, 55, 59, 65, 82, 83, 88, 95, 97, 104, 112, 113, 118, 119, 123, 127, 131, 142, 147, 177, 180, 185, 186, 204, 207, 215, 218, 220, 243, 246, 253, 257, 263, 270, 274, 280, 286, 287, 299, 330, 332, 334, 335, 339, 343, 354, 365, 372, 379, 381, 384, 388, 392, 400, 413

Offset

1,2

Links

Robert Israel, Table of n, a(n) for n = 1..10000

Example

a(3) = 8 is a term because A000203(8) = 15 = 3*5 and 8+15+(3+5) = 31 is prime.

Maple

filter:= proc(n) local s; s:= numtheory:-sigma(n);
  isprime(n + s + add(t[1]*t[2], t=ifactors(s)[2]))
end proc:

Crossrefs

Cf. A000203, A001414, A343413.

Sequence in context: A067789 A225400 A180867 * A063218 A104656 A179993

Adjacent sequences: A343409 A343410 A343411 * A343413 A343414 A343415

Keyword

nonn

Author

J. M. Bergot and Robert Israel, Apr 14 2021

Status

approved