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 A232485 #22 Aug 05 2024 09:55:50 %S A232485 3,6,12,14,18,26,38,62,74,102,102,102,102,102,102,102,102,102,102,102, %T A232485 102,102,102,102,102,102,102,102,102,102,102,102,102,102,102,102,102, %U A232485 102,102,102,102,102,102,102,102,102,102,102,102,102,102,102,102,102,102,102,102,102,102,102,102,102,102,102,102,102 %N A232485 a(1) = 3; thereafter a(n+1) = a(n) + product of digits of a(n). %D A232485 GCHQ, The GCHQ Puzzle Book, Penguin, 2016. See page 36. %H A232485 <a href="/index/Coi#Colombian">Index entries for Colombian or self numbers and related sequences</a> %H A232485 <a href="/index/Rec#order_01">Index entries for linear recurrences with constant coefficients</a>, signature (1). %t A232485 NestList[#+Times@@IntegerDigits[#]&,3,70] (* _Harvey P. Dale_, Jul 02 2017 *) %Y A232485 Cf. A063108, A230102, A232486. %K A232485 nonn,base %O A232485 1,1 %A A232485 _N. J. A. Sloane_, Nov 29 2013