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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A140890 a(n) = sum of primes in {10*n-9, 10*n-7, 10*n-3, 10*n-1}.

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%I A140890 #26 Feb 19 2021 01:54:27
%S A140890 10,60,52,68,131,112,128,223,172,97,420,113,127,407,149,308,330,352,
%T A140890 181,780,0,211,679,472,241,508,532,548,564,293,307,941,0,668,696,712,
%U A140890 367,752,772,397,810,419,421,1303,892,457,1391,479,487,990,1012,0,1044,0
%N A140890 a(n) = sum of primes in {10*n-9, 10*n-7, 10*n-3, 10*n-1}.
%F A140890 a(n) = (10n-9) isprime (10n-9) + (10n-7) isprime (10n-7) + (10n-3) isprime (10n-3) + (10n-1) isprime (10n-1), where isprime = A010051. - _M. F. Hasler_, Jun 15 2008
%e A140890 a(1) = 3 + 7 = 10.
%e A140890 a(11) = 101 + 103 + 107 + 109 = 420.
%e A140890 a(21) = 0 (there are no primes in {201, 203, 207, 209}).
%t A140890 f[n_]:=Plus@@Select[10n-{9,7,3,1},PrimeQ]; Table[f[n],{n,60}] (* _Ray Chandler_, Feb 20 2009 *)
%o A140890 (PARI) a(n)=(10*n-9)*isprime(10*n-9) + (10*n-7)*isprime(10*n-7) + (10*n-3)*isprime(10*n-3) + (10*n-1)*isprime(10*n-1) \\ _M. F. Hasler_, Jun 15 2008
%Y A140890 Cf. A030430, A030431, A030432, A030433.
%K A140890 nonn
%O A140890 1,1
%A A140890 _Juri-Stepan Gerasimov_, Jul 06 2008
%E A140890 Corrected and extended by _Ray Chandler_, Feb 20 2009