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A369447
Lexicographically earliest infinite sequence such that a(i) = a(j) => A001065(i) = A001065(j) and A342671(i) = A342671(j), for all i, j >= 1.
1
1, 2, 3, 4, 3, 5, 3, 6, 7, 8, 3, 9, 3, 10, 11, 12, 3, 13, 3, 14, 15, 16, 3, 17, 18, 19, 20, 21, 3, 22, 3, 23, 12, 24, 25, 26, 3, 27, 28, 29, 3, 30, 3, 31, 32, 33, 3, 34, 35, 36, 37, 38, 3, 39, 28, 40, 41, 42, 3, 43, 3, 44, 45, 46, 47, 48, 3, 49, 50, 51, 3, 52, 3, 31, 53, 54, 55, 56, 3, 57, 58, 59, 3, 60, 61, 62, 63, 64, 3, 65, 37, 66
OFFSET
1,2
COMMENTS
Restricted growth sequence transform of the ordered pair [A001065(n), A342671(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; };
A003961(n) = { my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); };
Aux369447(n) = [sigma(n)-n, gcd(sigma(n), A003961(n))];
v369447 = rgs_transform(vector(up_to, n, Aux369447(n)));
A369447(n) = v369447[n];
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jan 25 2024
STATUS
approved