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A373482
Numbers k for which A003415(k) is a multiple of A001414(k), where A003415 is the arithmetic derivative, and A001414 is the sum of prime factors with multiplicity.
3
1, 4, 6, 8, 9, 10, 14, 15, 16, 21, 22, 25, 26, 27, 32, 33, 34, 35, 36, 38, 39, 46, 49, 51, 55, 57, 58, 62, 64, 65, 69, 72, 74, 77, 81, 82, 85, 86, 87, 91, 93, 94, 95, 100, 106, 111, 112, 115, 118, 119, 121, 122, 123, 125, 126, 128, 129, 133, 134, 141, 142, 143, 145, 146, 155, 156, 158, 159, 161, 166, 169, 177, 178
OFFSET
1,2
LINKS
MATHEMATICA
Select[Range[180],
Divisible[If[#1 < 2, 0, #1 Total[#2/#1 & @@@ #2]],
Total[Times @@@ #2]] & @@
{#, FactorInteger[#]} &] (* Michael De Vlieger, Jun 08 2024 *)
PROG
(PARI) isA373482 = A373481;
CROSSREFS
Cf. A001414, A003415, A373481 (characteristic function).
After the initial 1, positions of 0's in A373480.
Subsequences: A176540 (k such that A003415(k) = A001414(k)), A346041.
Sequence in context: A330991 A180366 A340656 * A346041 A341614 A323644
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jun 08 2024
STATUS
approved