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A050662 a(n) is smallest number such that number of primes produced according to rules stipulated in Honaker's A048853 is n. 12
90, 20, 2, 1, 29, 23, 11, 13, 117, 101, 107, 387, 177, 357, 1001, 4221, 10759, 11487, 42497, 42189, 317721, 984417, 344253, 1851759, 14040341, 15848679, 125367697, 139367847, 1044394659, 2214409197, 2909053719, 14485875423, 1167555543, 111738007953 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(32) > 10^10. a(33) = 1167555543. a(34) > 10^10. - Donovan Johnson, May 08 2010

a(35) > 3*10^11. - Oscar Volpatti, Aug 06 2020

LINKS

Table of n, a(n) for n=1..34.

MAPLE

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

CROSSREFS

Cf. A048853, first terms of A050652-A050661, A050673.

Sequence in context: A247899 A247902 A052999 * A236180 A332427 A033410

Adjacent sequences:  A050659 A050660 A050661 * A050663 A050664 A050665

KEYWORD

nonn,base,more

AUTHOR

Patrick De Geest, Jul 15 1999

EXTENSIONS

a(25)-a(31) and a(33) from Donovan Johnson, May 08 2010

a(32) and a(34) from Oscar Volpatti, Aug 06 2020

STATUS

approved

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Last modified September 29 07:28 EDT 2020. Contains 337425 sequences. (Running on oeis4.)