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 A210470 Powerful numbers (A001694) which can be written as the sum of two relatively prime 3-powerful numbers different from 1. 0
 841, 968, 2312, 3528, 5041, 5776, 12769, 14884, 16641, 45125, 51984, 109561, 123823, 157609, 168921, 207576, 373321, 450241, 498436, 609725, 711828, 731025, 798768 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 REFERENCES Jean-Marie de Konninck, Those Fascinating Numbers, Amer. Math. Soc., 2009. Alonso Del Arte, Posting to the Sequence Fans Mailing List, Mar 10 2011. LINKS FORMULA { a in A001694: a=b+c and b,c >1 and b,c in A036966 and gcd(b,c)=1}. - R. J. Mathar, May 01 2013 EXAMPLE 841 = 216+625 ; 968 = 343+625 ; 2312=125+2187; MAPLE isA210470 := proc(n)     if isA001694(n) then         for i from 2 do             p3 := A036966(i) ;             if p3+2 > n then                 return false;             end if;             p3comp := n-p3 ;             if isA036966(p3comp) and igcd(p3, p3comp) = 1 then                 # print(n, p3, p3comp) ;                 return true;             end if;         end do:         return false;     else         return false;     end if; end proc: for n from 1 do     if isA210470(n) then         printf("%d, ", n) ;     end if; end do: # R. J. Mathar, May 01 2013 CROSSREFS Sequence in context: A269894 A252780 A159690 * A108324 A133496 A253599 Adjacent sequences:  A210467 A210468 A210469 * A210471 A210472 A210473 KEYWORD nonn,more AUTHOR N. J. A. Sloane, Apr 22 2013 STATUS approved

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Last modified January 17 14:57 EST 2020. Contains 330958 sequences. (Running on oeis4.)