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A070282 a(1) = 1; a(2) = 2; a(n) = [sum of digits of a(n-1)]^[sum of digits of a(n-2)] for n > 2. 1
1, 2, 2, 4, 16, 2401, 823543, 6103515625, 193630125104980427932766033374162714624, 121679161406852748316898260838871037524995421354288562472420444438058627601 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

The next term, a(11), has 381 digits. - Harvey P. Dale, Jan 08 2013

LINKS

Table of n, a(n) for n=1..10.

MATHEMATICA

a[n_] := (Plus @@ IntegerDigits[a[n - 1]])^(Plus @@ IntegerDigits[a[n - 2]]); a[1] = 1; a[2] = 2; Table[ a[n], {n, 1, 10}]

nxt[{a_, b_}]:={b, Total[IntegerDigits[b]]^Total[IntegerDigits[a]]}; Transpose[ NestList[nxt, {1, 2}, 10]][[1]] (* Harvey P. Dale, Jan 08 2013 *)

CROSSREFS

Sequence in context: A171163 A129614 A070283 * A267218 A051285 A079556

Adjacent sequences:  A070279 A070280 A070281 * A070283 A070284 A070285

KEYWORD

base,nonn

AUTHOR

Joseph L. Pe, May 09 2002

EXTENSIONS

Edited by Robert G. Wilson v, May 14 2002

STATUS

approved

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Last modified December 8 12:07 EST 2019. Contains 329862 sequences. (Running on oeis4.)