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A081249 Partial sums of A081134. 5
0, 1, 1, 2, 4, 7, 9, 10, 10, 11, 13, 16, 20, 25, 31, 38, 46, 55, 63, 70, 76, 81, 85, 88, 90, 91, 91, 92, 94, 97, 101, 106, 112, 119, 127, 136, 146, 157, 169, 182, 196, 211, 227, 244, 262, 281, 301, 322, 344, 367, 391, 416, 442, 469, 495, 520, 544, 567, 589, 610, 630 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

LINKS

Table of n, a(n) for n=1..61.

Klaus Brockhaus, Illustration for A081134, A081249, A081250 and A081251

FORMULA

a(n) = sum{j=1..n, A081134(j)}.

EXAMPLE

First seven terms of A081134 are 0,1,0,1,2,3,2, so a(7) = 9.

MATHEMATICA

Accumulate[Flatten[Table[Join[Range[0, 3^n], Range[3^n-1, 1, -1]], {n, 0, 4}]]] (* Harvey P. Dale, Sep 21 2016 *)

PROG

(PARI) {s=0; for(n=1, 62, p=3^floor(0.1^25+log(n)/log(3)); print1(s=s+min(n-p, 3*p-n), ", "))}

CROSSREFS

Sequence in context: A071790 A199465 A288305 * A327217 A327207 A279934

Adjacent sequences:  A081246 A081247 A081248 * A081250 A081251 A081252

KEYWORD

easy,nonn

AUTHOR

Klaus Brockhaus, Mar 17 2003

STATUS

approved

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Last modified May 16 21:59 EDT 2021. Contains 343954 sequences. (Running on oeis4.)