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A209685 Sum of last two digits of n. 3

%I

%S 0,1,2,3,4,5,6,7,8,9,1,2,3,4,5,6,7,8,9,10,2,3,4,5,6,7,8,9,10,11,3,4,5,

%T 6,7,8,9,10,11,12,4,5,6,7,8,9,10,11,12,13,5,6,7,8,9,10,11,12,13,14,6,

%U 7,8,9,10,11,12,13,14,15,7,8,9,10,11,12,13,14,15,16,8,9,10,11,12,13,14,15,16,17,9,10,11,12,13,14,15,16,17,18,0,1,2,3,4,5,6,7,8,9,1

%N Sum of last two digits of n.

%C Note that "Sum of last three digits of n" takes the same values as this sequence for n <= 99 (but not for n = 100). "Sum of last three digits of n" repeats every 1000 terms, while this sequence repeats every 100 values. Analogs are obvious for "sum of the last 4 values of n" which repeats every 10^4 values. - _Jonathan Vos Post_, Mar 12 2012 [First sentence corrected by _N. J. A. Sloane_, Feb 12 2017]

%H Indranil Ghosh, <a href="/A209685/b209685.txt">Table of n, a(n) for n = 0..1000</a>

%H <a href="/index/Rec#order_100">Index entries for linear recurrences with constant coefficients</a>, signature (0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1).

%e 99->9+9=18, 100->0+0=0.

%o (PARI) a(n)=n%100\10+n%10 \\ _Charles R Greathouse IV_, Mar 11 2012

%o (Python)

%o def A209685(n):

%o ....if n<=9:return n

%o ....return int(str(n)[-1])+int(str(n)[-2]) # _Indranil Ghosh_, Feb 12 2017

%Y Cf. A209674, A080463. Differs from A007953 and A076314 at n=100.

%K nonn,base,easy

%O 0,3

%A _N. J. A. Sloane_, Mar 11 2012

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Last modified August 24 14:25 EDT 2019. Contains 326284 sequences. (Running on oeis4.)