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A134872 Product of n-th Mersenne prime and 2^n. 0
6, 28, 248, 2032, 262112, 8388544, 67108736 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(1)= 6, the first perfect number. a(2)= 28, the second perfect number. a(3)=248, the dimensions of E_8.

LINKS

Table of n, a(n) for n=1..7.

FORMULA

a(n)=A000668(n) * 2^n.

EXAMPLE

a(3)=248 because the third Mersenne prime is 31, 2^3=8 and 31*8=248.

CROSSREFS

Cf. A061029. Powers of 2: A000079. Mersenne primes: A000668.

Sequence in context: A206708 A216413 A090898 * A281003 A049603 A035527

Adjacent sequences:  A134869 A134870 A134871 * A134873 A134874 A134875

KEYWORD

nonn

AUTHOR

Omar E. Pol, Nov 25 2007

EXTENSIONS

Spelling corrected and n(7) added by Jason G. Wurtzel, Aug 22 2010

STATUS

approved

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Last modified December 5 22:37 EST 2019. Contains 329782 sequences. (Running on oeis4.)