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 A069620 #5 May 21 2025 19:02:09 %S A069620 8,83,283,2833,32833,328331,2328331,232833127,3232833127,323283312749, %T A069620 14323283312749,1432328331274927,281432328331274927, %U A069620 28143232833127492741,3628143232833127492741,36281432328331274927411 %N A069620 a(1) = 8; a(2n) = smallest prime that is a right concatenation of a(2n-1) and a number with no insignificant zeros and a(2n+1) = smallest prime ending in ( the least significant digits) a(2n-1). Alternate left and right concatenation yielding primes. %e A069620 a(4) = 2833 starting with a(3) = 283 and a(5) = 32833 ending in a(4) = 2833. %Y A069620 Cf. A053582, A069605, A069606, A069607, A069608, A069609, A069610, A069611, A069613, A069614, A069615, A069616, A069617, A069618, A069619. %K A069620 nonn,base %O A069620 1,1 %A A069620 _Amarnath Murthy_, Mar 27 2002 %E A069620 More terms from Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Mar 30 2003