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A125119 Values of repunits with odd length L in base (L+3)/2 representation. 1
1, 13, 341, 19531, 2015539, 329554457, 78536544841, 25736391511831, 11111111111111111, 6115909044841454629, 4182283628124518315101, 3479492117784426363920483, 3461445831219105624193478971 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Central terms of the triangle in A125118: a(n)=A125118(2*n-1,n).
LINKS
Eric Weisstein's World of Mathematics, Repunit
FORMULA
a(n) = Sum((n+1)^k: 0<=k<=2*(n-1)).
EXAMPLE
a(4) = [1111111]_5 = (((((5+1)*5+1)*5+1)*5+1)*5+1)*5+1 = 19531.
CROSSREFS
Sequence in context: A041312 A096717 A296679 * A160396 A253125 A297070
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Nov 21 2006
STATUS
approved

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Last modified March 28 09:04 EDT 2024. Contains 371240 sequences. (Running on oeis4.)