A067484 Powers of 6 with initial digit 6.

6, 60466176, 609359740010496, 6140942214464815497216, 61886548790943213277031694336, 623673825204293256669089197883129856, 6285195213566005335561053533150026217291776, 63340286662973277706162286946811886609896461828096

Offset: 1

Author

Amarnath Murthy, Feb 09 2002

Keywords

• base
• easy
• nonn

Comments

The geometric progression formula a(n)=10077696*a(n-1) does NOT hold if n=20, 40, 59, 79, 98, etc. - R. J. Mathar, Jun 24 2009

Links

• Muniru A Asiru, Table of n, a(n) for n = 1..89
• Tanya Khovanova, Non Recursions

Crossrefs

Cf. A067480, A067481, A067482, A067483.

Programs

GAP

k:=6;; Filtered(List([0..80],n->k^n),i->ListOfDigits(i)[1]=k); # Muniru A Asiru, Oct 18 2018

Maple

A067484 := proc(n) local p6,p,a ; if n = 1 then 6; else p6 := procname(n-1) ; ifactors(p6)[2] ; p := op(2,op(1,%)) ; for a from p+1 do p6 := 6^a ; convert(%,base,10) ; if op(-1,%) = 6 then RETURN(p6) ; fi; od: fi; end: # R. J. Mathar, Jun 24 2009

Mathematica

Select[6^Range[100],First[IntegerDigits[#]]==6&] (* Harvey P. Dale, Aug 14 2018 *)

Extensions

More terms from Benoit Cloitre, Feb 22 2002

a(8) from Harvey P. Dale, Aug 14 2018

Offset changed to 1 by Muniru A Asiru, Oct 19 2018