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A140423 a(n) = Sum_{k=1..n} k^(2^(n+1-k)). 0
1, 5, 26, 354, 72379, 4338080215, 18448597098193762724, 340282370354622283774333836315916425060, 115792089237316207213755562747271079374483128445080168204415615259394085515413 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(10) has 155 digits and is too large to show here. - Emeric Deutsch, Jul 20 2008

LINKS

Table of n, a(n) for n=1..9.

MAPLE

a:=proc(n) options operator, arrow: sum(k^(2^(n+1-k)), k=1..n) end proc: seq(a(n), n=1..8); # Emeric Deutsch, Jul 20 2008

MATHEMATICA

Table[Sum[k^(2^(n+1-k)), {k, n}], {n, 10}] (* Harvey P. Dale, Mar 08 2012 *)

CROSSREFS

Sequence in context: A295114 A060516 A077537 * A324419 A090644 A196951

Adjacent sequences:  A140420 A140421 A140422 * A140424 A140425 A140426

KEYWORD

nonn

AUTHOR

Leroy Quet, Jun 18 2008

EXTENSIONS

More terms from Emeric Deutsch, Jul 20 2008

STATUS

approved

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Last modified October 17 21:17 EDT 2021. Contains 348065 sequences. (Running on oeis4.)