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A166666 Totally multiplicative sequence with a(p) = 8p+1 for prime p. 1
1, 17, 25, 289, 41, 425, 57, 4913, 625, 697, 89, 7225, 105, 969, 1025, 83521, 137, 10625, 153, 11849, 1425, 1513, 185, 122825, 1681, 1785, 15625, 16473, 233, 17425, 249, 1419857, 2225, 2329, 2337, 180625, 297, 2601, 2625, 201433, 329, 24225, 345 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..10000

FORMULA

Multiplicative with a(p^e) = (8p+1)^e. If n = Product p(k)^e(k) then a(n) = Product (8*p(k)+1)^e(k).

MATHEMATICA

a[1] = 1; a[n_] := (fi = FactorInteger[n]; Times @@ ((8*fi[[All, 1]] + 1)^fi[[All, 2]])); Table[a[n], {n, 1, 100}](* G. C. Greubel, May 22 2016 *)

CROSSREFS

Sequence in context: A294689 A263540 A183346 * A147445 A129910 A259075

Adjacent sequences:  A166663 A166664 A166665 * A166667 A166668 A166669

KEYWORD

nonn,mult

AUTHOR

Jaroslav Krizek, Oct 18 2009

STATUS

approved

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Last modified December 11 07:18 EST 2019. Contains 329914 sequences. (Running on oeis4.)