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 A075058 #33 Jun 07 2023 04:37:00 %S A075058 1,2,3,7,13,23,47,97,193,383,769,1531,3067,6133,12269,24533,49069, %T A075058 98129,196247,392503,785017,1570007,3140041,6280067,12560147,25120289, %U A075058 50240587,100481167,200962327,401924639,803849303,1607698583,3215397193,6430794373 %N A075058 Lexicographically earliest infinite sequence of distinct positive numbers with the property that every positive integer is a sum of distinct terms (see algorithm below). %C A075058 This sequence starts with a(0)=1, subsequent terms a(n) for n > 0 being obtained by selecting the greatest prime <= 1 + Sum_{i=0..n-1} a(i). This ensures that the sequence has the required property because Sum_{i=0..n-1} a(i) >= a(n) - 1, for all n >= 0 and a(0)=1, is a necessary and sufficient condition for it to hold. %H A075058 Charles R Greathouse IV, <a href="/A075058/b075058.txt">Table of n, a(n) for n = 0..1000</a> %H A075058 Wikipedia, <a href="http://en.wikipedia.org/wiki/Complete_sequence">"Complete" sequence</a>. [Wikipedia calls a sequence "complete" (sic) if every positive integer is a sum of distinct terms. This name is extremely misleading and should be avoided. - _N. J. A. Sloane_, May 20 2023] %F A075058 a(n) = (greatest prime) <= 1 + Sum_{i=0..n-1} a(i). %F A075058 a(n) ~ k*2^n, with k roughly 0.748643. - _Charles R Greathouse IV_, Apr 05 2013 %e A075058 Given that the first 7 terms of the sequence are 1,2,...,23,47 then a(8)=(greatest prime) <= (1+2+...+23,47) + 1 = 97, hence a(8)=97. %t A075058 prevprime[n_Integer] := (j=n; While[!PrimeQ[j], j--]; j) aprime[0]=1; aprime[n_Integer] := (aprime[n] = prevprime[Sum[aprime[m], {m, 0, n - 1}] + 1]); Table[aprime[p], {p, 0, 50}] %t A075058 a[0] = 1; a[n_] := a[n] = NextPrime[Sum[a[k], {k, 0, n-1}]+2, -1]; Table[a[n], {n, 0, 33}] (* _Jean-François Alcover_, Sep 30 2013 *) %o A075058 (PARI) print1(s=1);for(n=1,20,k=precprime(s+1);print1(", "k);s+=k) \\ _Charles R Greathouse IV_, Apr 05 2013 %Y A075058 Cf. A068524, A007924, A066352, A200947. %K A075058 nonn %O A075058 0,2 %A A075058 _Amarnath Murthy_, Sep 07 2002 %E A075058 Entry revised by _Frank M Jackson_, Dec 03 2011 %E A075058 Edited by _N. J. A. Sloane_, May 20 2023