A134872 Product of n-th Mersenne prime and 2^n.

6, 28, 248, 2032, 262112, 8388544, 67108736, 549755813632, 1180591620717411302912, 633825300114114700748351601664, 332306998946228968225951765070084096, 696898287454081973172991196020261297057792

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..12.

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.

Mathematica

Table[(2^MersennePrimeExponent[n]-1)2^n, {n, 12}] (* Harvey P. Dale, Mar 26 2023 *)

Crossrefs

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

Sequence in context: A336565 A216413 A090898 * A281003 A049603 A333927

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

More terms from Harvey P. Dale, Mar 26 2023

Status

approved