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Digits d in decimal expansion of n replaced with d-th prime (replacing each 0 digit with a 1).
7

%I #16 Nov 07 2019 22:07:53

%S 1,2,3,5,7,11,13,17,19,23,21,22,23,25,27,211,213,217,219,223,31,32,33,

%T 35,37,311,313,317,319,323,51,52,53,55,57,511,513,517,519,523,71,72,

%U 73,75,77,711,713,717,719,723,111,112,113,115,117,1111,1113,1117,1119

%N Digits d in decimal expansion of n replaced with d-th prime (replacing each 0 digit with a 1).

%H Harvey P. Dale, <a href="/A048380/b048380.txt">Table of n, a(n) for n = 0..1000</a>

%p a:= n-> (l-> parse(cat(seq(`if`(l[-i]=0, 1, ithprime(l[-i])),

%p i=1..nops(l)))))(convert(n, base, 10)):

%p seq(a(n), n=0..80); # _Alois P. Heinz_, Nov 07 2019

%t Table[FromDigits[Flatten[IntegerDigits/@(If[#==0,1,Prime[#]]&/@ IntegerDigits[ n])]], {n,0,60}] (* _Harvey P. Dale_, Sep 02 2018 *)

%Y Cf. A000040, A008578, A048381, A048383, A048384.

%K nonn,base

%O 0,2

%A _Patrick De Geest_, Mar 15 1999

%E Name clarified by _Jon E. Schoenfield_, Oct 13 2019