Search: id:A076312 Results 1-1 of 1 results found. %I A076312 %S A076312 0,2,4,6,8,10,12,14,16,18,1,3,5,7,9,11,13,15,17,19,2,4,6,8,10,12,14,16, %T A076312 18,20,3,5,7,9,11,13,15,17,19,21,4,6,8,10,12,14,16,18,20,22,5,7,9,11, %U A076312 13,15,17,19,21,23,6,8,10,12,14,16,18,20,22,24,7,9,11,13,15,17,19,21 %N A076312 floor(n/10) + 2*(n mod 10). %C A076312 (n==0 modulo 19) iff (a(n)==0 modulo 19); applied recursivly, this property provides a divisibility test for numbers given in base 10 notation. %D A076312 Karl Menninger, Rechenkniffe, Vandenhoeck & Ruprecht in Goettingen (1961), 79A. %F A076312 G.f.: -x(17x^9-2-2x-2x^2-2x^3-2x^4-2x^5-2x^6-2x^7-2x^8)/((1-x)^2(1+x)(x^4+x^3+x^2+x+1)(x^4-x^3+x^2-x+1)). a(n)=A059995(n)+2*A010879(n). [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jan 24 2009] %e A076312 26468 is not a multiple of 19, as 26468 -> 2646+2*8=2662 -> 266+2*2=270 -> 27+2*0=27=19*1+8, therefore the answer is NO; %e A076312 is 12882 divisible by 19? 12882 -> 1288+2*2=1292 -> 129+2*2=133 -> 13+2*3=19, therefore the answer is YES. %Y A076312 Cf. A008601, A076309, A076310, A076311. %Y A076312 Sequence in context: A076309 A088133 A115299 this_sequence A061762 A136614 A097586 %Y A076312 Adjacent sequences: A076309 A076310 A076311 this_sequence A076313 A076314 A076315 %K A076312 nonn %O A076312 0,2 %A A076312 Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Oct 06 2002 Search completed in 0.001 seconds