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a(n) is the number of times in the format hh:mm that can be represented in a 7-segment display by using only n segments (version A006942).
4

%I #6 Oct 23 2022 23:30:08

%S 1,2,4,14,25,37,70,105,123,153,186,182,156,139,119,79,35,9,1

%N a(n) is the number of times in the format hh:mm that can be represented in a 7-segment display by using only n segments (version A006942).

%C Since 8 <= A357970(n) <= 26 the sequence is finite and begins with offset 8.

%H <a href="/index/Ca#calculatordisplay">Index entries for sequences related to calculator display</a>

%t a055643[n_]:=FromDigits@ Apply[Join, PadLeft[#, 2] & /@ IntegerDigits@ IntegerDigits[n, 60]]; a006942[n_] := Plus @@ (IntegerDigits@ n /. {0 -> 6, 1 -> 2, 2 -> 5, 3 -> 5, 7 -> 3, 8 -> 7, 9 -> 6}); a[n_]:=a006942[a055643[n]]+6(4-Ceiling[Log10[a055643[n]+1]]); Table[Count[Join[{24},Array[a,1439]],n],{n,8,26}]

%Y Histogram of A357970.

%Y Cf. A006942, A008588, A055642, A055643.

%Y Variants: A357997, A357998, A357999, A358000.

%K nonn,base,easy,fini,full

%O 8,2

%A _Stefano Spezia_, Oct 23 2022