A369259 Lexicographically earliest infinite sequence such that a(i) = a(j) => A003557(i) = A003557(j), A048250(i) = A048250(j) and A342671(i) = A342671(j), for all i, j >= 1.

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 15, 23, 24, 25, 26, 27, 28, 29, 21, 30, 31, 32, 31, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 29, 31, 43, 44, 45, 46, 47, 48, 49, 46, 50, 51, 52, 53, 54, 55, 39, 56, 57, 58, 59, 60, 61, 62, 59, 46, 63, 64, 65, 66, 67, 62, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 59

Offset

1,2

Comments

Restricted growth sequence transform of the triplet [A003557(j), A048250(i), A342671(n)].

For all i, j >= 1:

a(i) = a(j) => A323368(i) = A323368(j) => A291751(i) = A291751(j),

a(i) = a(j) => A369260(i) = A369260(j) => A286603(i) = A286603(j).

Links

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

Index entries for sequences computed from indices in prime factorization

Index entries for sequences related to sigma(n)

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; };
A003557(n) = (n/factorback(factor(n)[, 1]));
A003961(n) = { my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };
A048250(n) = if(n<1, 0, sumdiv(n, d, if(core(d)==d, d)));
A342671(n) = gcd(sigma(n), A003961(n));
Aux369259(n) = [A003557(n), A048250(n), A342671(n)];
v369259 = rgs_transform(vector(up_to, n, Aux369259(n)));
A369259(n) = v369259[n];

Crossrefs

Cf. A000203, A001615, A003557, A003961, A048250, A286603, A291751, A369260.

Differs from related A296089 and A323368 for the first time at n=79, where a(79) = 69, while A296089(79) = A323368(79) = 51.

Sequence in context: A296088 A296089 A323368 * A080686 A036218 A172275

Adjacent sequences: A369256 A369257 A369258 * A369260 A369261 A369262

Keyword

nonn

Author

Antti Karttunen, Jan 25 2024

Status

approved