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%I #17 Mar 11 2021 17:30:11
%S 3,6,9,12,15,18,21,24,18,21,15,18,21,24,27,30,33,36,30,33,27,30,33,36,
%T 39,42,45,48,42,45,39,42,45,48,51,54,57,60,54,57,51,54,57,60,63,66,69,
%U 72,66,69,63,66,69,72,75,78,81,84,78,81,75,78,81,84,87,90,93,96,90,93
%N a(n) = n + digital sum(n-1) + digital sum(n+1).
%F a(n) = n + A007953(n-1) + A007953(n+1)
%e a(8) = 8 +ds(7) +ds(9) = 7+8+9 = 24;
%e a(15) = 15+ds(14)+ds(16) = 15+5+7 = 27;
%e a(26) = 26+ds(25)+ds(27) = 26+7+9 = 42.
%t Table[n+Total[IntegerDigits[n-1]]+Total[IntegerDigits[n+1]],{n,70}] (* _Harvey P. Dale_, Jun 24 2011 *)
%o (Python)
%o def A160943(n): return n+sum(int(d) for d in str(n-1))+sum(int(d) for d in str(n+1)) # _Chai Wah Wu_, Mar 11 2021
%o (PARI) a(n) = n + sumdigits(n-1) + sumdigits(n+1); \\ _Michel Marcus_, Mar 11 2021
%Y Cf. A007953, A062028, A160939.
%K nonn,base
%O 1,1
%A _Claudio Meller_, May 30 2009