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A336297 Prime numbers p such that equation x = p*sopf(x) (where sopf(x) is the sum of distinct prime factors of x) has exactly 1 solution in positive integers. 3
2, 61, 97, 113, 151, 173, 241, 277, 317, 353, 389, 449, 457, 593, 601, 607, 653, 673, 683, 727, 733, 797, 907, 929, 941, 947, 953, 977, 997, 1021, 1051, 1087, 1153, 1181, 1193, 1217, 1249, 1307, 1321, 1361, 1373, 1409, 1433, 1489, 1493, 1523, 1553, 1579, 1597, 1609, 1627 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..51.

Vladimir Letsko, Mathematical Marathon, Problem 227 (in Russian).

EXAMPLE

4 is the unique integer x such that x = 2*sopf(x), a prime, so 2 is a term.

CROSSREFS

Cf. A008472, A336098, A336099, A336296.

Sequence in context: A130411 A262079 A222009 * A041449 A261944 A142729

Adjacent sequences:  A336294 A336295 A336296 * A336306 A336307 A336308

KEYWORD

nonn

AUTHOR

Vladimir Letsko, Jul 16 2020

STATUS

approved

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Last modified September 30 05:03 EDT 2020. Contains 337435 sequences. (Running on oeis4.)