login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A120929 Partial sums of n^(n^2), A002489. 1
1, 2, 18, 19701, 4294986997, 298023228171940122, 10314424798788558774343889178, 256923577521069192513410265783009965210785, 6277101735386681020759366944276858929512621227473999723681 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

After 2, can this ever be prime? This is to A001923 Sum k^k, k=1..n, as k^k^k is to k^k.

LINKS

Table of n, a(n) for n=0..8.

FORMULA

a(n) = sum[i=0..n] i^i^i. a(n) = sum[i=0..n] i^(i^2). a(n) = sum[i=0..n] (i^i)^i. In this sequence, we formally define 0^0 = 1.

EXAMPLE

a(0) = 1 because A002489(0) is given formally as 0^0^0 = 1.

a(1) = 2 because 1 + 1^1^1 = 1 + 1 = 2.

a(2) = 18 because 2 + 2^2^2 = 2 + 16 = 18.

a(3) = 19701 because 18 + 3^3^3 = 18 + 19683 = 19701.

a(4) = 4294986997 = 19701 + 4^4^4 = 19701 + 4294967296.

MATHEMATICA

Accumulate[Join[{1}, Table[n^(n^2), {n, 9}]]] (* Harvey P. Dale, Apr 10 2014 *)

CROSSREFS

Cf. A001923, A002489, A002488, A001329, A002488, A023813, A076113, A090588.

Sequence in context: A276092 A191554 A066361 * A007184 A067765 A293242

Adjacent sequences:  A120926 A120927 A120928 * A120930 A120931 A120932

KEYWORD

easy,nonn

AUTHOR

Jonathan Vos Post, Aug 18 2006

EXTENSIONS

More terms from Harvey P. Dale, Apr 10 2014

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified July 17 23:21 EDT 2019. Contains 325109 sequences. (Running on oeis4.)