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A123873 Similar to A123872 but with a(0)=4 as seed. 1
4, 6, 26, 126, 3126, 15625001 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

REFERENCES

G. Balzarotti and P. P. Lava, Le sequenze di numeri interi, Hoepli, 2008, p. 99.

LINKS

Table of n, a(n) for n=0..5.

EXAMPLE

a(0)=4;

a(1)=6 because 4*6 = 24;

a(2)=26 because 24*26 = 624;

a(3)=126 because 624*126 = 78624;

a(4)=3126 because 78624*3126 = 245778624;

a(5)=15625001 because 245778624*15625001 = 3840291245778624.

MAPLE

P:=proc(q, h) local a, b, k, n; a:=h; b:=ilog10(a)+1; print(h);

for k from 1 to 10 do for n from 2 to q do

if ((a*n) mod 10^b)=a then print(n); a:=a*n; b:=ilog10(a)+1;

break; fi; od; od; end: P(10^9, 4);

CROSSREFS

Sequence in context: A159557 A176756 A054094 * A193689 A099941 A074120

Adjacent sequences:  A123870 A123871 A123872 * A123874 A123875 A123876

KEYWORD

nonn,base,more

AUTHOR

Paolo P. Lava and Giorgio Balzarotti, Oct 16 2006, Oct 24 2006

STATUS

approved

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Last modified August 20 14:36 EDT 2019. Contains 326152 sequences. (Running on oeis4.)