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A176023 a(1) = 13, a(n) = square of sum of previous terms. 0
13, 169, 33124, 1109289636, 1230597389647535364, 1514369938137587812499677175361189636, 2293316309534841541915473293317407055631848366256764867236421660610435364 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Sqrt(a(n+1)/a(n)) is an integer. Except first 3 terms, the terms alternately end in 36 and 64.

LINKS

Table of n, a(n) for n=1..7.

FORMULA

a(n+1) = (Sum_{i=1..n} a(i))^2, with a(1)=13. - Paolo P. Lava, Apr 23 2010

MAPLE

P:=proc(i) local a, s, n; a:=13; print(13); s:=13; for n from 0 by 1 to i do a:=s^2; print(a); s:=s+a; od; end: P(100); # Paolo P. Lava, Apr 23 2010

CROSSREFS

Sequence in context: A228389 A020533 A176596 * A067220 A057684 A053153

Adjacent sequences:  A176020 A176021 A176022 * A176024 A176025 A176026

KEYWORD

easy,nonn

AUTHOR

Giovanni Teofilatto, Apr 06 2010

STATUS

approved

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Last modified December 5 09:47 EST 2020. Contains 338945 sequences. (Running on oeis4.)