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A302299 Values of A000010(m) such that no solutions share the same prime signature. 1
1, 2, 4, 6, 8, 10, 16, 18, 22, 28, 30, 32, 42, 44, 46, 52, 54, 56, 58, 64, 66, 70, 78, 82, 92, 100, 102, 104, 106, 110, 116, 126, 128, 130, 136, 138, 140, 148, 150, 162, 164, 166, 172, 178, 184, 190, 196, 198, 204, 208, 210, 212, 220, 222, 226, 228, 238, 250, 256, 260 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..60.

Max Alekseyev, PARI scripts for various problems (see invphi.gp there).

EXAMPLE

1 is a term as the only solutions A000010(1) and A000010(2) do not share the same prime signature.

2 is a term as the only solutions A000010(3), A000010(4), and A000010(6) do not share the same prime signature.

12 is not a term since A000010(21) = A000010(26) are solutions and the prime signature of 21 and 26 is {1,1}.

PROG

(PARI) signa(n) = {my(f = factor(n)); vecsort(f[, 2]); }

isok(n) = {my(vinv = invphi(n), vinvs = vector(#vinv, k, signa(vinv[k]))); return (#vinvs == #Set(vinvs)); }

lista(nn) = {for (n=1, nn, if (istotient(n) && isok(n), print1(n, ", ")); ); } \\ Michel Marcus, Apr 08 2018

CROSSREFS

Complement of A302297 w.r.t. A002202. Cf. A000010.

Sequence in context: A102470 A057195 A088007 * A227992 A175299 A088008

Adjacent sequences:  A302296 A302297 A302298 * A302300 A302301 A302302

KEYWORD

nonn

AUTHOR

Torlach Rush, Apr 04 2018

EXTENSIONS

More terms from Michel Marcus, Apr 09 2018

STATUS

approved

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Last modified May 9 13:35 EDT 2021. Contains 343742 sequences. (Running on oeis4.)