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A331312 a(n) = A225546(n) / A293442(n). 2
1, 1, 2, 1, 8, 2, 128, 1, 3, 8, 32768, 2, 2147483648, 128, 16, 1, 9223372036854775808, 3, 170141183460469231731687303715884105728, 8, 256, 32768, 57896044618658097711785492504343953926634992332820282019728792003956564819968, 2, 27, 2147483648, 6, 128 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
LINKS
FORMULA
a(n) = A225546(n) / A293442(n).
Multiplicative, with a(prime(i)^j) = A019565(j)^A000225(i-1).
PROG
(PARI)
A019565(n) = {my(j, v); factorback(Mat(vector(if(n, #n=vecextract(binary(n), "-1..1")), j, [prime(j), n[j]])~))}; \\ From A019565
A331312(n) = { my(f=factor(n)); for (i=1, #f~, my(p=f[i, 1]); f[i, 1] = A019565(f[i, 2]); f[i, 2] = (2^(primepi(p)-1))-1; ); factorback(f); };
CROSSREFS
Sequence in context: A257777 A011208 A001281 * A232535 A065826 A286899
KEYWORD
nonn,mult
AUTHOR
Antti Karttunen, Jan 21 2020
STATUS
approved

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Last modified June 7 10:16 EDT 2024. Contains 373162 sequences. (Running on oeis4.)