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A115922
Numbers k such that k and 2*k, taken together are pandigital.
6
13485, 13548, 13845, 14538, 14685, 14835, 14853, 14865, 15486, 16485, 18546, 18645, 20679, 20769, 20793, 23079, 26709, 26907, 27069, 27093, 27309, 29067, 29073, 29307, 30729, 30792, 30927, 31485, 32079, 32709, 32907, 34851, 35148, 35481, 38145, 38451
OFFSET
1,1
COMMENTS
Sequence contains 48 terms, the largest being 48651.
If leading zeros are permitted, there are 12 additional terms: 6729, 6792, 6927, 7269, 7293, 7329, 7692, 7923, 7932, 9267, 9273, 9327. - Harvey P. Dale, Feb 09 2014
LINKS
Nathaniel Johnston, Table of n, a(n) for n = 1..48 (full sequence)
EXAMPLE
13485 and 26970=13485*2 together contain all the 10 digits once.
MAPLE
for n from 12345 to 49382 do d:=[op(convert(n, base, 10)), op(convert(2*n, base, 10))]: pandig:=true: for k from 0 to 9 do if(numboccur(k, d)<>1)then pandig:=false: break: fi: od: if(pandig)then print(n): fi: od: # Nathaniel Johnston, May 31 2011
MATHEMATICA
onehalfQ[n_]:=FromDigits[Take[n, 5]]/FromDigits[Take[n, -5]]==1/2; FromDigits[ Take[#, 5]]&/@Select[Permutations[Range[0, 9]], onehalfQ] (* This program generates the full 60-term sequence, with leading zeros permitted, of which this sequence is a subset -- see Comments *) (* Harvey P. Dale, Feb 09 2014 *)
PROG
(PARI) {for(n=10234, 49876, #Set(digits(n))==5||next; #Set(digits(n*2))==5 && #Set(concat(digits(n), digits(n*2)))==10 && print1(n", "))} \\ M. F. Hasler, Feb 08 2014
KEYWORD
nonn,base,fini,full
AUTHOR
Giovanni Resta, Feb 06 2006
STATUS
approved