A115425 -id:A115425 - cp's OEIS frontend

A115589 Multiply first digit by k, append result to sequence; multiply second digit by k, append result to sequence; multiply third digit by k, append result to sequence; etc. a(1)=1, k=7 case.

1, 7, 49, 28, 63, 14, 56, 42, 21, 7, 28, 35, 42, 28, 14, 14, 7, 49, 14, 56, 21, 35, 28, 14, 14, 56, 7, 28, 7, 28, 49, 28, 63, 7, 28, 35, 42, 14, 7, 21, 35, 14, 56, 7, 28, 7, 28, 35, 42, 49, 14, 56, 49, 14, 56, 28, 63, 14, 56, 42, 21, 49, 14, 56, 21, 35, 28, 14, 7, 28, 49, 14, 7, 21

Offset: 1

Zak Seidov, Mar 09 2006

All terms are evidently multiples of 7: 7, 14, ..., 63. Is the sequence periodic? Some repeating patterns are obvious, e.g., 63, 7, 28, 35, 42, but no cycle appears.

Cf. A115425.

ss=s={1};Do[d=7s[[i]];AppendTo[ss,d];s=Flatten[{s,IntegerDigits[d]}],{i,200}];ss

A117826 First four terms of the sequence are doubled, then those numbers are tripled and then those numbers are quadrupled, etc.

Original entry on oeis.org

1, 2, 3, 4, 2, 4, 6, 8, 6, 12, 18, 24, 24, 48, 72, 96, 120, 240, 360, 480, 720, 1440, 2160, 2880, 5040, 10080, 15120, 20160, 40320, 80640, 120960, 161280, 362880, 725760, 1088640, 1451520, 3628800, 7257600, 10886400, 14515200, 39916800, 79833600

Offset: 1

Robert G. Wilson v, Apr 25 2006

nonn

Cf. A000142, A115425.

Table[n!{1, 2, 3, 4}, {n, 11}] // Flatten

a(4n-3) = A000142(n). a(4n-2)=2*A000142(n)=A052849(n), a(4n-1)=3*A000142(n)=A052560(n), a(4n)=4*A000142(n)=2*A052849(n)=A052578(n).

cp's OEIS Frontend

A115589 Multiply first digit by k, append result to sequence; multiply second digit by k, append result to sequence; multiply third digit by k, append result to sequence; etc. a(1)=1, k=7 case.

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