

A146763


Rank of terms ending in 0 in A061039.


1



0, 4, 10, 14, 20, 24, 30, 34, 40, 44, 50, 54, 60, 64, 70, 74, 80, 84, 90, 94, 100, 104, 110, 114, 120, 124, 130, 134, 140, 144, 150, 154, 160, 164, 170, 174, 180, 184, 190, 194, 200, 204, 210, 214, 220, 224, 230, 234, 240, 244, 250, 254, 260, 264, 270, 274
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

0,2


COMMENTS

From Paschen spectrum of hydrogen.
Numbers that are congruent to 0 or 4 mod 10.  Philippe Deléham, Oct 18 2011


LINKS

Table of n, a(n) for n=0..55.
Index entries for linear recurrences with constant coefficients, signature (1,1,1).


FORMULA

a(n) = 10*na(n1)6 (with a(0)=0).  Vincenzo Librandi, Nov 26 2010
a(n) = Sum_k>=0 {A030308(n,k)*b(k)} with b(0)=4 and b(k)=5*2^k=A020714(k) for k>0.  Philippe Deléham, Oct 18 2011
a(n) = (1+(1)^n+10*n)/2. a(n)=a(n1)+a(n2)a(n3). G.f.: x*(4+6*x) / ((1x)^2*(1+x)).  Colin Barker, May 14 2012


MATHEMATICA

Select[Range[0, 100], MemberQ[{0, 4}, Mod[#, 10]] &] (* K G Teal, Dec 02 2014 *)


CROSSREFS

Sequence in context: A310411 A310412 A310413 * A310414 A190346 A001581
Adjacent sequences: A146760 A146761 A146762 * A146764 A146765 A146766


KEYWORD

nonn,base,easy


AUTHOR

Paul Curtz, Nov 02 2008


STATUS

approved



