A369357 Numbers k such that there exists a number p such that k - p = sopfr(k + p) but no number q exists such that q - k = sopfr(q + k), where sopfr(m) is the sum of the primes dividing m, with repetition.

7, 12, 18, 20, 21, 23, 27, 36, 38, 42, 44, 60, 64, 71, 78, 88, 96, 102, 104, 107, 108, 111, 126, 128, 132, 133, 140, 141, 142, 148, 149, 152, 153, 158, 174, 177, 182, 183, 192, 198, 202, 204, 206, 207, 211, 226, 228, 234, 237, 242, 244, 249, 252, 258, 264, 268, 282, 292, 293, 308, 312, 314, 318

Offset

1,1

Comments

These numbers terminate the different series given in A369354.

Links

Scott R. Shannon, Table of n, a(n) for n = 1..10000

Example

21 is a term as 21 - 11 = 10 and sopfr(21 + 11) = sopfr(32) = 10, but no number q exists such that q - 21 = sopfr(q + 21).

Crossrefs

Cf. A001414, A369354, A369355, A369356, A369812, A369981, A369348, A369349.

Sequence in context: A272808 A092094 A064665 * A142337 A131912 A247159

Adjacent sequences: A369354 A369355 A369356 * A369358 A369359 A369360

Keyword

nonn

Author

Scott R. Shannon, Jan 25 2024

Status

approved