A099539 Sum of the first n decimal places of sqrt(2).

4, 5, 9, 11, 12, 15, 20, 26, 28, 31, 38, 41, 41, 50, 55, 55, 59, 67, 75, 75, 76, 82, 90, 98, 105, 107, 111, 113, 113, 122, 128, 137, 145, 145, 152, 160, 165, 171, 180, 186, 193, 194, 202, 209, 214, 217, 224, 230, 239, 243, 251, 251, 258, 261, 262, 269, 275, 281

Offset: 1

Author

Mark Hudson (mrmarkhudson(AT)hotmail.com), Oct 22 2004

Keywords

• base
• easy
• nonn

Comments

Cf. A099538 for a version of this sequence resulting from including all digits of sqrt(2) and not just the digits after the decimal point.

Examples

			Decimal places of sqrt(2) are 41421356237... so sums are 4, 4+1, 4+1+4, 4+1+4+2,... which gives 4, 5, 9, 11, ...
		

Links

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

Crossrefs

Cf. A099538 and A099534, A099535, A099536, A099537, A039918, A046974, A046975 for analogous sequences based on other constants.

Programs

Mathematica

Accumulate[Rest[RealDigits[N[Sqrt[2],70]][[1]]]] (* Harvey P. Dale, Dec 12 2010 *)

Formula

a(n) = A099538(n+1) - 1.