A318893 Filter sequence combining the prime signature of n (A046523) with Euler totient function (A000010).

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

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 * A338497 A137317 A308702

Adjacent sequences: A318890 A318891 A318892 * A318894 A318895 A318896

Keyword

nonn

Author

Antti Karttunen, Sep 16 2018

Status

approved