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A319525 Completely multiplicative with a(prime(k)) = prime(2*k - 1) (where prime(k) denotes the k-th prime). 3
1, 2, 5, 4, 11, 10, 17, 8, 25, 22, 23, 20, 31, 34, 55, 16, 41, 50, 47, 44, 85, 46, 59, 40, 121, 62, 125, 68, 67, 110, 73, 32, 115, 82, 187, 100, 83, 94, 155, 88, 97, 170, 103, 92, 275, 118, 109, 80, 289, 242, 205, 124, 127, 250, 253, 136, 235, 134, 137, 220 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

This sequence is a permutation of {1} union A066208.

See A297002 for a similar sequence.

LINKS

Table of n, a(n) for n=1..60.

FORMULA

a(n) = A064989(A297002(n)).

a(n) >= n with equality iff n is a power of 2 (A000079).

PROG

(PARI) a(n) = my (f=factor(n)); prod(i=1, #f~, prime(2*primepi(f[i, 1]) - 1)^f[i, 2])

CROSSREFS

Cf. A000079, A066208, A297002.

Sequence in context: A072403 A010078 A074639 * A338459 A343035 A002314

Adjacent sequences:  A319522 A319523 A319524 * A319526 A319527 A319528

KEYWORD

nonn,mult

AUTHOR

Rémy Sigrist, Sep 22 2018

STATUS

approved

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Last modified July 25 23:39 EDT 2021. Contains 346294 sequences. (Running on oeis4.)