A061830 Multiples of 5 having only even digits.

0, 20, 40, 60, 80, 200, 220, 240, 260, 280, 400, 420, 440, 460, 480, 600, 620, 640, 660, 680, 800, 820, 840, 860, 880, 2000, 2020, 2040, 2060, 2080, 2200, 2220, 2240, 2260, 2280, 2400, 2420, 2440, 2460, 2480, 2600, 2620, 2640, 2660, 2680, 2800, 2820, 2840

Offset: 0

Author

Amarnath Murthy, May 29 2001

Keywords

• nonn
• base
• easy

Examples

			220 = 5*44 is a term having all even digits.
		

Links

• Harvey P. Dale, Table of n, a(n) for n = 0..1000
• Index entries for 10-automatic sequences.
• Index entries for linear recurrences with constant coefficients, signature (1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1).

Crossrefs

Cf. A061829.

Programs

Mathematica

Select[5*Range[0,2000],And@@EvenQ[IntegerDigits[#]]&] (* or *) LinearRecurrence[ {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,-1},{0,20,40,60,80,200,220,240,260,280,400,420,440,460,480,600,620,640,660,680,800,820,840,860,880,2000},50] (* Harvey P. Dale, Feb 24 2014 *)

PARI

is(n)=n%10==0 && #setintersect(Set(digits(n)), [1,3,5,7,9])==0 \\ Charles R Greathouse IV, Feb 15 2017

Formula

a(0)=0, a(1)=20, a(2)=40, a(3)=60, a(4)=80, a(5)=200, a(6)=220, a(7)=240, a(8)=260, a(9)=280, a(10)=400, a(11)=420, a(12)=440, a(13)=460, a(14)=480, a(15)=600, a(16)=620, a(17)=640, a(18)=660, a(19)=680, a(20)=800, a(21)=820, a(22)=840, a(23)=860, a(24)=880, a(25)=2000, a(n)=a(n-1)+ a(n-25)- a(n-26). - Harvey P. Dale, Feb 24 2014

Extensions

More terms from Larry Reeves (larryr(AT)acm.org), May 30 2001