

A271448


Numbers which are the sum of their proper divisors containing the digit 2.


8




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

Table of n, a(n) for n=1..6.


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 * A176089 A261112 A219082
Adjacent sequences: A271445 A271446 A271447 * A271449 A271450 A271451


KEYWORD

nonn,base,less,more


AUTHOR

Giovanni Resta, May 02 2016


STATUS

approved



