OFFSET
1,1
FORMULA
MAPLE
A002808 := proc(n) option remember ; local a ; if n = 1 then 4; else for a from A002808(n-1)+1 do if not isprime(a) then RETURN(a) ; fi ; od: fi ; end:
isA060254 := proc(n) local i, sComp ; if isprime(n) then for i from 1 do sComp := A002808(i)+A002808(i+1) ; if sComp = n then RETURN(i); elif sComp > n then RETURN(-1) ; fi ; od: else -1 ; fi ; end:
A046665 := proc(n) local a, ifs ; a := 0 ; ifs := seq(op(1, i), i=ifactors(n)[2]) ; max(ifs)-min(ifs) ; end:
isA135170 := proc(p) local i ; i := isA060254(p) ; if i > 0 then A111426(i) + A111426(i+1) ; isprime(%) ; else false ; fi ; end:
for n from 1 to 300 do p := ithprime(n) ; if isA135170(p) then printf("%d, ", p) ; fi ; od: # R. J. Mathar, Feb 19 2008
CROSSREFS
KEYWORD
nonn
AUTHOR
Giovanni Teofilatto, Feb 14 2008
EXTENSIONS
Corrected and extended by R. J. Mathar, Feb 19 2008
More precise definition by R. J. Mathar, Sep 17 2009
STATUS
approved