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Sum of three consecutive reversed primes.
1

%I #30 Feb 06 2021 21:49:23

%S 10,15,23,49,113,193,194,215,137,178,100,121,122,143,204,146,187,109,

%T 130,151,172,233,215,278,481,1103,1903,1913,1933,1163,1583,1793,2603,

%U 2023,1843,1263,1873,1493,2103,1523,1343,763,1373,2173,1894,1425

%N Sum of three consecutive reversed primes.

%H Vincenzo Librandi, <a href="/A171444/b171444.txt">Table of n, a(n) for n = 1..1000</a>

%F a(n) = r(p(n)) + r(p(n+1)) + r(p(n+2)) where p(n) is the n-th prime number and r(n) is the number obtained by the reversal of the digits of n (e.g., r(1230) = 321).

%e (from primes 11, 13, and 17): 11 + 31 + 71 = 113;

%e (from primes 13, 17, and 19): 31 + 71 + 91 = 193;

%e (from primes 173, 179, and 181): 371 + 971 + 181 = 1523.

%t r[n_] := FromDigits[Reverse[IntegerDigits[n]]]; Table[r[Prime[n]] + r[Prime[n+1]] + r[Prime[n+2]], {n, 50}]

%Y Cf. A034961, A004087.

%K nonn,base

%O 1,1

%A _Vincenzo Librandi_, Dec 09 2009

%E More terms from _Matthew Conroy_, Dec 28 2010