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A318892 Filter sequence combining the prime signature of n (A046523) with A289625. 2
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, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 35, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 44, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 68, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 75, 90 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Restricted growth sequence transform of A289628.
For all i, j: a(i) = a(j) => A318893(i) = A318893(j).
LINKS
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
A289625(n) = { my(m=1, p=2, v=znstar(n)[2]); for(i=1, length(v), m *= p^v[i]; p = nextprime(p+1)); (m); };
A318892aux(n) = [A046523(n), A289625(n)];
v318892 = rgs_transform(vector(up_to, n, A318892aux(n)));
A318892(n) = v318892[n];
CROSSREFS
Sequence in context: A188462 A352530 A058321 * A323404 A056064 A274055
KEYWORD
nonn
AUTHOR
Antti Karttunen, Sep 16 2018
STATUS
approved

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Last modified August 29 21:13 EDT 2024. Contains 375518 sequences. (Running on oeis4.)