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 A088469 #26 Sep 14 2017 15:31:08 %S A088469 0,0,0,0,0,0,0,0,0,1,17,1,1,1,1,1,1,1,1,1,1,15,1,1,1,1,1,1,1,1,1,1,13, %T A088469 1,1,1,1,1,1,1,1,1,1,11,1,1,1,1,1,1,1,1,1,1,9,1,1,1,1,1,1,1,1,1,1,7,1, %U A088469 1,1,1,1,1,1,1,1,1,5,1,1,1,1,1,1,1,1,1,1,3,1,1,1,1,1,1,1,1,1 %N A088469 Number of distinct lunar prime divisors of n. %C A088469 a(n) is the number of lunar primes p that are lunar divisors of n. (Multiplicity is not taken into account. Each prime is counted at most once.) %H A088469 D. Applegate, <a href="/A087061/a087061.txt">C program for lunar arithmetic and number theory</a> [Note: we have now changed the name from "dismal arithmetic" to "lunar arithmetic" - the old name was too depressing] %H A088469 D. Applegate, M. LeBrun and N. J. A. Sloane, <a href="http://arxiv.org/abs/1107.1130">Dismal Arithmetic</a> [Note: we have now changed the name from "dismal arithmetic" to "lunar arithmetic" - the old name was too depressing] %H A088469 D. Applegate, M. LeBrun, N. J. A. Sloane, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL14/Sloane/carry2.html">Dismal Arithmetic</a>, J. Int. Seq. 14 (2011) # 11.9.8. %H A088469 <a href="/index/Di#dismal">Index entries for sequences related to dismal (or lunar) arithmetic</a> %e A088469 10 = 9*90 and 90 is prime. 90 is the only prime divisor of 10, so a(10) = 1. %Y A088469 Cf. A088471, A088472, A087097. %K A088469 nonn %O A088469 1,11 %A A088469 _David Applegate_, Nov 11 2003