OFFSET
1,1
COMMENTS
If we had a(1) = 1 (instead of 3), then this would be fully multiplicative with a(prime(k)) = prime(k+2) (see A357852). - Antti Karttunen, Jan 10 2020
REFERENCES
From a puzzle proposed by Marc LeBrun.
LINKS
Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
FORMULA
MATHEMATICA
a[1] = 3; a[n_] := With[{f = FactorInteger[n]}, Times @@ (Prime[PrimePi[f[[All, 1]]]+2]^f[[All, 2]])]; Array[a, 60] (* Jean-François Alcover, Jun 19 2015 *)
PROG
(Haskell)
a045966 1 = 3
a045966 n = product $ zipWith (^)
(map a101300 $ a027748_row n) (a124010_row n)
-- Reinhard Zumkeller, Jun 03 2013, Dec 23 2011
(PARI) A045966(n) = if(1==n, 3, my(f = factor(n)); for(i=1, #f~, f[i, 1] = nextprime(1+nextprime(1+f[i, 1]))); factorback(f)); \\ Antti Karttunen, Jan 10 2020
CROSSREFS
A059896 is used to express relationship between terms of this sequence.
A357852 is a slightly better version. - N. J. A. Sloane, Oct 29 2022
KEYWORD
easy,nonn,nice
AUTHOR
EXTENSIONS
More terms from David W. Wilson
STATUS
approved