Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #20 Aug 07 2020 02:11:18
%S 90,20,2,1,29,23,11,13,117,101,107,387,177,357,1001,4221,10759,11487,
%T 42497,42189,317721,984417,344253,1851759,14040341,15848679,125367697,
%U 139367847,1044394659,2214409197,2909053719,14485875423,1167555543,111738007953
%N a(n) is smallest number such that number of primes produced according to rules stipulated in Honaker's A048853 is n.
%C a(32) > 10^10. a(33) = 1167555543. a(34) > 10^10. - _Donovan Johnson_, May 08 2010
%C a(35) > 3*10^11. - _Oscar Volpatti_, Aug 06 2020
%p A048853 := proc(n::integer) local resul,ddigs,d,c,tmp ; resul := 0 ; ddigs := convert(n,base,10) ; for d from 1 to nops(ddigs) do for c from 0 to 9 do if c = 0 and d = nops(ddigs) then continue ; else if c <> op(d,ddigs) then tmp := [op(1..d-1,ddigs),c,op(d+1..nops(ddigs),ddigs)] ; tst := sum(op(i,tmp)*10^(i-1),i=1..nops(tmp)) ; if isprime(tst) then resul := resul+1 ; fi ; fi ; fi ; od : od ; RETURN(resul) ; end: A050662 := proc(n::integer) local i; for i from 1 to 10000000 do if A048853(i) = n then RETURN(i) ; fi ; od ; RETURN(-1) ; end : for n from 1 to 90 do print(A050662(n)) ; od ; # _R. J. Mathar_, Apr 25 2006
%Y Cf. A048853, first terms of A050652-A050661, A050673.
%K nonn,base,more
%O 1,1
%A _Patrick De Geest_, Jul 15 1999
%E a(25)-a(31) and a(33) from _Donovan Johnson_, May 08 2010
%E a(32) and a(34) from _Oscar Volpatti_, Aug 06 2020