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 A271448 Numbers which are the sum of their proper divisors containing the digit 2. 8
 546, 39312, 60168, 534688, 2281353180, 272240989636 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(7) > 10^12. For each digit d=0..9 there is a corresponding sequence in OEIS (see Crossrefs), except for d=1, because up to 10^12, only 2654635632 is equal to the sum of its proper divisors which contain the digit 1. LINKS EXAMPLE The proper divisors of 546 are 1, 2, 3, 6, 7, 13, 14, 21, 26, 39, 42, 78, 91, 182, and 273. Since 2+21+26+42+182+273 = 546, 546 is a term. MATHEMATICA Select[Range[10^6], # == Plus @@ Select[Most@ Divisors@#, MemberQ[ IntegerDigits@ #, 2] &] &] CROSSREFS Cf. A059461, A059462, A059463, A059464, A059465, A059466, A059467, A059468. Sequence in context: A002606 A047637 A286440 * A347203 A176089 A261112 Adjacent sequences:  A271445 A271446 A271447 * A271449 A271450 A271451 KEYWORD nonn,base,less,more AUTHOR Giovanni Resta, May 02 2016 STATUS approved

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Last modified December 9 06:07 EST 2021. Contains 349627 sequences. (Running on oeis4.)