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.
%I A276087 #12 Oct 16 2019 02:12:03
%S A276087 2,3,6,5,30,125,18,45,150,7,1050,343,1250,2625,7350,16807,1650,847,
%T A276087 43218,3465,27731550,3195731,1183724850,435930295269007,17794411250,
%U A276087 7105308412125,3782866198615350,2709490941157,6237907125450,161696170950365051,10,75,750,175,294,12005,126,2205,51450,11,565950,1331,21008750,9904125,6225450,161051,1002614947950,190333
%N A276087 a(n) = A276086(A276086(n)).
%H A276087 Antti Karttunen, <a href="/A276087/b276087.txt">Table of n, a(n) for n = 0..210</a>
%F A276087 a(n) = A276086(A276086(n)).
%F A276087 Other identities. For all n >= 0:
%F A276087 a(A143293(n)) = A000040(2+n).
%t A276087 Block[{b = MixedRadix[Reverse@ Prime@ Range@ 12], f}, f[n_] := Times @@ Power @@@ # &@ Transpose@{Prime@ Range@ Length@ #, Reverse@ #} &@ IntegerDigits[n, b]; Array[Nest[f, #, 2] &, 48, 0]] (* _Michael De Vlieger_, Oct 15 2019 *)
%o A276087 (Scheme) (define (A276087 n) (A276086 (A276086 n)))
%Y A276087 Cf. A000040, A002110, A143293, A276086.
%K A276087 nonn,base
%O A276087 0,1
%A A276087 _Antti Karttunen_, Aug 21 2016