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A222221
In the number n, replace all (decimal) digits '1' with '4' and vice versa.
1
0, 4, 2, 3, 1, 5, 6, 7, 8, 9, 40, 44, 42, 43, 41, 45, 46, 47, 48, 49, 20, 24, 22, 23, 21, 25, 26, 27, 28, 29, 30, 34, 32, 33, 31, 35, 36, 37, 38, 39, 10, 14, 12, 13, 11, 15, 16, 17, 18, 19, 50, 54, 52, 53, 51, 55, 56, 57, 58, 59, 60, 64, 62, 63, 61, 65, 66, 67, 68, 69, 70, 74, 72, 73, 71, 75
OFFSET
0,2
COMMENTS
The map which is applied to primes in A171020.
LINKS
MATHEMATICA
a[n_]:= IntegerDigits[n]/.{1->4, 4->1} // FromDigits; Table[a[n], {n, 0, 80}] (* Vincenzo Librandi, Jul 29 2013 *)
PROG
(PARI) A222221(n, d=[0, 4, 2, 3, 1, 5, 6, 7, 8, 9])=sum(i=1, #n=digits(n), d[n[i]+1]*10^(#n-i)) \\ gives correct value for n=0 iff d[1]=0, since digits(0)=[] in PARI (v.2.6)
KEYWORD
nonn,base,easy
AUTHOR
M. F. Hasler, Feb 12 2013
STATUS
approved