A324818 Lexicographically earliest sequence such that a(i) = a(j) => A009194(i) = A009194(j) and A324396(i) = A324396(j) for all i, j.

1, 2, 2, 2, 2, 3, 2, 2, 4, 5, 2, 6, 2, 5, 7, 8, 2, 9, 2, 5, 8, 10, 2, 11, 12, 5, 13, 14, 2, 3, 2, 2, 7, 5, 13, 2, 2, 5, 4, 15, 2, 3, 2, 6, 7, 5, 2, 6, 16, 2, 7, 5, 2, 3, 2, 17, 4, 5, 2, 11, 2, 10, 13, 2, 13, 18, 2, 5, 7, 5, 2, 9, 2, 5, 13, 6, 19, 3, 2, 5, 4, 5, 2, 14, 16, 20, 21, 22, 2, 23, 24, 6, 13, 10, 25, 26, 2, 2, 7, 8, 2, 18, 2, 5, 21

Offset

1,2

Comments

Restricted growth sequence transform of the ordered pair [A009194(n), A324396(n)], that is, of the ordered pair [A009194(n), A009194(A156552(n))].

Links

Antti Karttunen, Table of n, a(n) for n = 1..10000 (based on Hans Havermann's factorization of A156552)

Index entries for sequences related to binary expansion of n

Index entries for sequences computed from indices in prime factorization

Index entries for sequences related to sigma(n)

Prog

(PARI)
up_to = 10000;
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; };
A009194(n) = gcd(n, sigma(n));
A156552(n) = {my(f = factor(n), p2 = 1, res = 0); for(i = 1, #f~, p = 1 << (primepi(f[i, 1]) - 1); res += (p * p2 * (2^(f[i, 2]) - 1)); p2 <<= f[i, 2]); res}; \\ From A156552
A324396(n) = gcd(A156552(n), A323243(n)); \\ Needs code also from A323243
v324818 = rgs_transform(vector(up_to, n, [A009194(n), A324396(n)]));
A324818(n) = v324818[n];

Crossrefs

Cf. A009194, A156552, A323243, A324396.

Sequence in context: A201375 A309865 A128764 * A233417 A299741 A074589

Adjacent sequences: A324815 A324816 A324817 * A324819 A324820 A324821

Keyword

nonn

Author

Antti Karttunen, Mar 17 2019

Status

approved