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A318893 Filter sequence combining the prime signature of n (A046523) with Euler totient function (A000010). 3
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 21, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 34, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 42, 48, 43, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 53, 70, 59, 71, 66, 72, 73, 74, 51, 75, 76, 77, 78, 79, 80, 81, 76, 82, 83, 71 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Restricted growth sequence transform of A286160.

For all i, j: a(i) = a(j) => A062355(i) = A062355(j).

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..65537

PROG

(PARI)

up_to = 65537;

rgs_transform(invec) = { my(om = Map(), outvec = vector(length(invec)), u=1); for(i=1, length(invec), if(mapisdefined(om, invec[i]), my(pp = mapget(om, invec[i])); outvec[i] = outvec[pp] , mapput(om, invec[i], i); outvec[i] = u; u++ )); outvec; };

A046523(n) = { my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i]); }; \\ From A046523

A318893aux(n) = [eulerphi(n), A046523(n)];

v318893 = rgs_transform(vector(up_to, n, A318893aux(n)));

A318893(n) = v318893[n];

CROSSREFS

Cf. A000010, A046523, A286160, A318839, A318892.

Cf. also A061468, A062355.

Sequence in context: A236851 A030545 A295886 * A137317 A308702 A326200

Adjacent sequences:  A318890 A318891 A318892 * A318894 A318895 A318896

KEYWORD

nonn

AUTHOR

Antti Karttunen, Sep 16 2018

STATUS

approved

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Last modified February 25 11:14 EST 2020. Contains 332233 sequences. (Running on oeis4.)