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A011262 In the prime factorization of n, increment odd powers and decrement even powers (multiplicative and self-inverse). 3
1, 4, 9, 2, 25, 36, 49, 16, 3, 100, 121, 18, 169, 196, 225, 8, 289, 12, 361, 50, 441, 484, 529, 144, 5, 676, 81, 98, 841, 900, 961, 64, 1089, 1156, 1225, 6, 1369, 1444, 1521, 400, 1681, 1764, 1849, 242, 75, 2116, 2209, 72, 7, 20, 2601, 338, 2809, 324, 3025, 784, 3249 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Paul Tek, Table of n, a(n) for n = 1..10000

Index entries for sequences that are permutations of the natural numbers

FORMULA

Multiplicative with f(p^k) = p^(k-1) if k even, p^(k+1) if k odd.

a(n) = product(A027748(n,k) ^ A103889(A124010(n,k)): k = 1..A001221(n)). - Reinhard Zumkeller, Jun 23 2013

MATHEMATICA

f[n_, k_] := n^(If[EvenQ[k], k - 1, k + 1]); Table[Times @@ f @@@ FactorInteger[n], {n, 57}] (* Jayanta Basu, Aug 14 2013 *)

PROG

(PARI) a(n)=my(f=factor(n)); return(prod(i=1, #f[, 1], f[i, 1]^(f[i, 2]-(-1)^f[i, 2]))) /* Paul Tek, Jun 01 2013 */

(Haskell)

a011262 n = product $ zipWith (^)

                      (a027748_row n) (map a103889 $ a124010_row n)

-- Reinhard Zumkeller, Jun 23 2013

CROSSREFS

Cf. A011264.

Sequence in context: A048758 A277802 A159253 * A073843 A073842 A136271

Adjacent sequences:  A011259 A011260 A011261 * A011263 A011264 A011265

KEYWORD

nonn,easy,mult

AUTHOR

Marc LeBrun

STATUS

approved

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Last modified March 26 10:42 EDT 2017. Contains 284111 sequences.