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A136428 First differences of A064770. 2
1, 0, 0, 1, 0, 0, 0, 0, 1, 7, 1, 0, 0, 1, 0, 0, 0, 0, 1, -3, 1, 0, 0, 1, 0, 0, 0, 0, 1, -3, 1, 0, 0, 1, 0, 0, 0, 0, 1, 7, 1, 0, 0, 1, 0, 0, 0, 0, 1, -3, 1, 0, 0, 1, 0, 0, 0, 0, 1, -3, 1, 0, 0, 1, 0, 0, 0, 0, 1, -3, 1, 0, 0, 1, 0, 0, 0, 0, 1, -3, 1, 0, 0, 1, 0, 0, 0, 0, 1, 7, 1, 0, 0, 1, 0, 0, 0, 0, 1, 67, 1, 0, 0, 1, 0, 0, 0, 0, 1, 7, 1, 0, 0, 1, 0, 0, 0, 0, 1, -3, 1, 0, 0, 1, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,10

COMMENTS

a(10*n+k) = 0 for k = 1, 2, 4, 5, 6, 7;

a(10*n+k) = 1 for k = 0, 3, 8;

a(100*n+10*k+9) = -3 for k = 1, 2, 4, 5, 6, 7;

a(100*n+10*k+9) = 7 for k = 0, 3, 8;

a(1000*n+100*k+99) = -33 for k = 1, 2, 4, 5, 6, 7;

a(1000*n+100*k+99) = 67 for k = 0, 3, 8.

LINKS

R. Zumkeller, Table of n, a(n) for n = 0..9999

FORMULA

a(n) = (2*A010052(m mod 10) - 1)*rounded(((1+A010052(m mod 10))*10^k)/3) where n = m*10^k - 1 with m mod 10 > 0.

CROSSREFS

Sequence in context: A157307 A036949 A059515 * A271697 A226371 A298937

Adjacent sequences:  A136425 A136426 A136427 * A136429 A136430 A136431

KEYWORD

sign

AUTHOR

Reinhard Zumkeller, Dec 30 2007

STATUS

approved

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Last modified February 23 07:28 EST 2020. Contains 332159 sequences. (Running on oeis4.)