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A270437
Multiplicative with a(p^e) = p^(e XOR 2e), where XOR is bitwise-xor.
6
1, 8, 27, 64, 125, 216, 343, 32, 729, 1000, 1331, 1728, 2197, 2744, 3375, 4096, 4913, 5832, 6859, 8000, 9261, 10648, 12167, 864, 15625, 17576, 243, 21952, 24389, 27000, 29791, 32768, 35937, 39304, 42875, 46656, 50653, 54872, 59319, 4000, 68921, 74088, 79507, 85184, 91125, 97336, 103823, 110592, 117649, 125000
OFFSET
1,2
COMMENTS
Multiplicative with a(p^e) = p^A048724(e), where A048724(e) = (e XOR 2e).
Multiples of 8 in the ring defined in A329329. - Peter Munn, Jan 17 2020
LINKS
FORMULA
a(1) = 1, for n > 1, a(n) = A020639(n)^A048724(A067029(n)) * a(A028234(n)).
Other identities. For all n >= 1:
A270418(a(n)) = 1, A270419(a(n)) = n.
a(n) = A329329(n,8) = A329329(8,n). - Peter Munn, Jan 17 2020
MATHEMATICA
f[p_, e_] := p^BitXor[2*e, e]; a[1] = 1; a[n_] := Times @@ f @@@ FactorInteger[n]; Array[a, 50] (* Amiram Eldar, Sep 07 2023 *)
PROG
(Scheme, with memoization-macro definec)
(definec (A270437 n) (cond ((= 1 n) 1) (else (* (expt (A020639 n) (A048724 (A067029 n))) (A270437 (A028234 n))))))
CROSSREFS
Cf. A262675 (same sequence sorted into ascending order).
Cf. also A270418, A270419, A270436 and permutation A273671.
Row 8 and column 8 of A329329.
Sequence in context: A213491 A276919 A076989 * A259603 A254521 A351985
KEYWORD
nonn,easy,mult
AUTHOR
Antti Karttunen, May 27 2016
EXTENSIONS
Name changed by Antti Karttunen, Sep 07 2023
STATUS
approved