A140528 Sum of digits of Mersenne prime exponents.

2, 3, 5, 7, 4, 8, 10, 4, 7, 17, 8, 10, 8, 13, 19, 7, 13, 13, 14, 13, 32, 23, 8, 29, 11, 16, 28, 23, 10, 19, 19, 38, 32, 37, 38, 29, 23, 41, 37, 28, 31, 41, 25, 38, 41, 28, 26, 41

Offset: 1

Author

Edmund Algeo, Jul 03 2008

Keywords

• nonn
• base
• more

Examples

			Since A000043(15) = 1279, a(15) = 1+2+7+9 = 19. - _Timothy L. Tiffin_, Jul 14 2021
		

Crossrefs

Cf. A000043, A007953.

Programs

Mathematica

Table[Plus @@ IntegerDigits[e], {e, MersennePrimeExponent[Range[47]]}] (* Amiram Eldar, Jul 16 2021 *)

Formula

a(n) = A007953(A000043(n)). - Michel Marcus, Jul 15 2021

Extensions

a(39)-a(40) corrected by and a(41)-a(47) from Timothy L. Tiffin, Jul 14 2021

a(48) from Amiram Eldar, Oct 18 2024