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A376714 Sum of squares of the decimal digits of the n-th prime.

%I A376714 #16 Oct 04 2024 15:49:14
%S A376714 4,9,25,49,2,10,50,82,13,85,10,58,17,25,65,34,106,37,85,50,58,130,73,
%T A376714 145,130,2,10,50,82,11,54,11,59,91,98,27,75,46,86,59,131,66,83,91,131,
%U A376714 163,6,17,57,89,22,94,21,30,78,49,121,54,102,69,77,94,58,11
%N A376714 Sum of squares of the decimal digits of the n-th prime.
%H A376714 Katie Khan, <a href="/A376714/b376714.txt">Table of n, a(n) for n = 1..10000</a>
%F A376714 a(n) = A003132(A000040(n)).
%e A376714 For n=7, the 7th prime = 17 and those digits 1^2 + 7^2 = 50 = a(7).
%t A376714 a[n_]:=Norm[IntegerDigits[Prime[n]]]^2; Array[a,64] (* _Stefano Spezia_, Oct 03 2024 *)
%o A376714 (PARI) a(n) = norml2(digits(prime(n))); \\ _Michel Marcus_, Oct 03 2024
%o A376714 (Python)
%o A376714 from sympy import prime
%o A376714 def A376714(n): return sum((0, 1, 4, 9, 16, 25, 36, 49, 64, 81)[int(d)] for d in str(prime(n)) if d>'0') # _Chai Wah Wu_, Oct 04 2024
%Y A376714 Cf. A000040, A003132, A007605.
%K A376714 nonn,base,easy
%O A376714 1,1
%A A376714 _Katie Khan_, Oct 02 2024