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A074459
Number of segments which change from display of a number n to the next number n+1 on a 7-segment display: version where '6', '7', '9' use 6, 4, resp. 5 segments.
2
4, 5, 2, 3, 3, 1, 4, 3, 2, 5, 4, 5, 2, 3, 3, 1, 4, 3, 2, 8, 4, 5, 2, 3, 3, 1, 4, 3, 2, 5, 4, 5, 2, 3, 3, 1, 4, 3, 2, 6, 4, 5, 2, 3, 3, 1, 4, 3, 2, 6, 4, 5, 2, 3, 3, 1, 4, 3, 2, 4, 4, 5, 2, 3, 3, 1, 4, 3, 2, 7, 4, 5, 2, 3, 3, 1, 4, 3, 2, 6, 4, 5, 2, 3, 3, 1, 4, 3, 2, 5
OFFSET
0,1
COMMENTS
The glyph variants used here are the same as in A074458 (other variants are described in A006942, A010371, A063720 and A277116). - M. F. Hasler, Jun 17 2020
FORMULA
For n % 10 < 9, a(n) = a(n % 9), where % is the modulo (remainder) operator. - M. F. Hasler, Jun 23 2020
EXAMPLE
Consider the representations of digits '0', '1' and '2' given below.
To change from 0 to 1, we need to delete 4 segments, from 1 to 2, we need to delete 1 segment and add 4 segments, so 5 segments in total are needed to be changed.
From M. F. Hasler, Jun 23 2020:
We consider the following 7-segment representations of the digits 0 - 9:
_ _ _ _ _ _ _ _
| | | _| _| |_| |_ |_ | | |_| |_|
|_| | |_ _| | _| |_| | |_| | .
To switch from displaying number 9 to displaying number 10, one has to activate 2 segments for the additional digit '1', and change 3 segments from the representation of '9' to get that of '0', whence a(9) = 2 + 3 = 5.
To switch from 19 to 20 one has a(19) = a(1) + 3 = 8. (End)
PROG
(PARI) apply( {A074459(n)=if(n%10<9, digits(452331432)[n%10+1], n>9, 3+self()(n\10), 5)}, [0..99]) \\ M. F. Hasler, Jun 23 2020
CROSSREFS
Cf. A074458.
Sequence in context: A085548 A329957 A379183 * A371747 A155793 A070593
KEYWORD
nonn,base
AUTHOR
Y. Kelly Itakura (yitkr(AT)mta.ca), Aug 22 2002
EXTENSIONS
Edited and terms for n > 8 added by M. F. Hasler, Jun 23 2020
STATUS
approved