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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.

A117527 Cumulative sums of int(prime*e) which are primes.

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%I A117527 #9 Mar 27 2025 13:58:12
%S A117527 5,13,109,641,757,4007,5387,7901,9349,11467,23297,33503,42193,57139,
%T A117527 76343,100213,209597,252583,261631,373621,424231,432287,503593,507961,
%U A117527 618593,699427,791489,825389,895243,943837,1212917,1455901,1573577
%N A117527 Cumulative sums of int(prime*e) which are primes.
%C A117527 Sometimes prime integer sums occur with consecutive primes, as 1601*e and 1607*e.
%F A117527 Beginning with the first prime, multiply by e, take integer, repeat, adding integer sums until a cumulative prime sum occurs. On the first prime, 2, the integer product is 5, prime. Continue to next integer product, add, until the next prime sum, 13.
%e A117527 The 4th cumulative sum of integer products is 641, prime.
%t A117527 Select[Accumulate[Floor[E*Prime[Range[500]]]],PrimeQ] (* _Harvey P. Dale_, Mar 27 2025 *)
%o A117527 (UBASIC)
%o A117527 10 Ct=1
%o A117527 20 B=nxtprm(B)
%o A117527 22 E=#e
%o A117527 30 C=int(B*E)
%o A117527 40 D=D+C
%o A117527 41 print Ct,B,C,D
%o A117527 50 if D=prmdiv(D) then print D:stop
%o A117527 55 Ct=Ct+1
%o A117527 60 goto 20
%Y A117527 Cf. A117528 A117503.
%K A117527 easy,nonn
%O A117527 1,1
%A A117527 _Enoch Haga_, Mar 25 2006