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 A072196 #19 Apr 11 2024 03:55:39 %S A072196 3,213,13653,873813,55924053,3579139413,229064922453,14660155037013, %T A072196 938249922368853,60047995031606613,3843071682022823253, %U A072196 245956587649460688213,15741221609565484045653,1007438183012190978921813,64476043712780222650996053,4126466797617934249663747413,264093875047547791978479834453 %N A072196 Multiples of 3 which on one operation of the Collatz function T (N -> 3N+1/2^r) yield the number 5. %H A072196 Michael De Vlieger, <a href="/A072196/b072196.txt">Table of n, a(n) for n = 1..554</a> %H A072196 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (65,-64). %F A072196 a(n) = (10*64^(n-1)-1)/3. - _Henry Bottomley_, Dec 02 2002 [Formula adapted to a change of offset by _Georg Fischer_, Apr 10 2024] %e A072196 (3*3+1)/2=5, (3*213+1)/2^7=5, etc. Thus multiples of 3 act as generators on the numbers in the Collatz domain. %p A072196 seq((10*64^(n-1)-1)/3, n=1..13); # _Georg Fischer_, Apr 10 2024 %t A072196 Array[(10*64^(# - 1) - 1)/3 &, 13] (* _Michael De Vlieger_, Apr 10 2024 *) %Y A072196 Cf. A139391, A072197. %K A072196 nonn,easy %O A072196 1,1 %A A072196 N. Rathankar (rathankar(AT)yahoo.com), Jul 03 2002 %E A072196 More terms from _Henry Bottomley_, Dec 02 2002