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A363031 a(n) = sigma(6*n+1). Sum of the divisors of 6*n+1, n >= 0.

%I A363031 #34 Sep 07 2023 12:47:59
%S A363031 1,8,14,20,31,32,38,44,57,72,62,68,74,80,108,112,98,104,110,144,133,
%T A363031 128,160,140,180,152,158,164,183,248,182,216,194,200,252,212,256,224,
%U A363031 230,288,242,280,288,304,324,272,278,284,307,360,352,308,314,360,434,332,338,400,350,432,381,368,374,380,576,432
%N A363031 a(n) = sigma(6*n+1). Sum of the divisors of 6*n+1, n >= 0.
%C A363031 The sum of divisors function A000203 seems to behave with a certain periodicity of period 6.
%H A363031 Michael De Vlieger, <a href="/A363031/b363031.txt">Table of n, a(n) for n = 0..9999</a>
%F A363031 a(n) = A000203(6*n+1).
%F A363031 a(n) = A000203(A016921(n)).
%t A363031 Array[DivisorSigma[1, 6 # + 1] &, 66, 0] (* _Michael De Vlieger_, Aug 27 2023 *)
%o A363031 (PARI) a(n) = sigma(6*n+1); \\ _Michel Marcus_, Aug 28 2023
%o A363031 (Python)
%o A363031 from sympy import divisor_sigma
%o A363031 def A363031(n): return divisor_sigma(6*n+1) # _Chai Wah Wu_, Sep 07 2023
%Y A363031 Partial sums give A363161.
%Y A363031 Cf. A000203, A016921, A224613.
%K A363031 nonn,easy
%O A363031 0,2
%A A363031 _Omar E. Pol_, May 18 2023