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A215736
a(n) is the first digit to appear n times in succession in a power of 7.
12
1, 1, 7, 9, 5, 7, 3, 1, 0, 0, 3, 4, 6, 5, 9, 1
OFFSET
1,3
MATHEMATICA
n = 1; x = 1; lst = {};
For[i = 1, i <= 10000, i++,
z = Split[IntegerDigits[x]]; a = Length /@ z; b = Max[a];
For[j = n, j <= b, j++,
AppendTo[lst, First[First[Part[z, First[Position[a, b]]]]]]; n++
]; x = 7 x ]; lst (* Robert Price, Mar 16 2019 *)
CROSSREFS
KEYWORD
nonn,base,hard,more
AUTHOR
V. Raman, Aug 22 2012
EXTENSIONS
a(10) added by V. Raman, Nov 23 2013
a(11)-a(13) from Giovanni Resta, Apr 19 2016
a(14)-a(15) from Bert Dobbelaere, Feb 15 2019
a(16) from Paul Geneau de Lamarlière, Jul 16 2024
STATUS
approved