A048384 -id:A048384 - cp's OEIS frontend

A048380 Digits d in decimal expansion of n replaced with d-th prime (replacing each 0 digit with a 1).

1, 2, 3, 5, 7, 11, 13, 17, 19, 23, 21, 22, 23, 25, 27, 211, 213, 217, 219, 223, 31, 32, 33, 35, 37, 311, 313, 317, 319, 323, 51, 52, 53, 55, 57, 511, 513, 517, 519, 523, 71, 72, 73, 75, 77, 711, 713, 717, 719, 723, 111, 112, 113, 115, 117, 1111, 1113, 1117, 1119

Offset: 0

Patrick De Geest, Mar 15 1999

Harvey P. Dale, Table of n, a(n) for n = 0..1000

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

a:= n-> (l-> parse(cat(seq(`if`(l[-i]=0, 1, ithprime(l[-i])),
             i=1..nops(l)))))(convert(n, base, 10)):
seq(a(n), n=0..80);  # Alois P. Heinz, Nov 07 2019

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

Name clarified by Jon E. Schoenfield, Oct 13 2019

A048383 Numbers k such that replacing each nonzero digit d with the d-th prime (replacing each 0 digit with a 1) yields a square.

Original entry on oeis.org

0, 13, 113, 2410, 4113, 6113, 8210, 14113, 23410, 28113, 33113, 34010, 35113, 51113, 62113, 71113, 76610, 81410, 93113, 101310, 117010, 123113, 242210, 253113, 279710, 298113, 300113, 351010, 513410, 529113, 544113, 616113, 634113

Offset: 1

Patrick De Geest, Mar 15 1999

			28113 = (2)(8)(1)(1)(3) -> (3)(19)(2)(2)(5) = 319225 = 565^2.

Cf. A000290, A048380, A048384.

Select[Range[0,650000],IntegerQ[Sqrt[FromDigits[Flatten[IntegerDigits/@ (If[#==0,1,Prime[#]]&/@IntegerDigits[#])]]]]&]  (* Harvey P. Dale, Mar 27 2011 *)

Definition edited and offset corrected by M. F. Hasler, Oct 11 2019

cp's OEIS Frontend

A048380 Digits d in decimal expansion of n replaced with d-th prime (replacing each 0 digit with a 1).

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