Search: id:A076543 Results 1-1 of 1 results found. %I A076543 %S A076543 1,3,6,2,7,13,20,12,3,13,24,12,25,39,54,38,55,37,56,36,57,79,102,78,53, %T A076543 79,52,24,53,83,114,82,115,149,184,148,185,223,262,222,263,305,348,304, %U A076543 259,305,352,304,255,205,256,204,257,203,258,202,259,317,376,316,377 %N A076543 Sum(k=1 to n) k*sqf(k); sqf(k)=1 if k is squarefree and sqf(k)=-1 otherwise. %C A076543 Suprisingly, first 12 terms are also in A074170. %Y A076543 Cf. A074170. %Y A076543 Sequence in context: A125717 A065232 A074170 this_sequence A005132 A064388 A064387 %Y A076543 Adjacent sequences: A076540 A076541 A076542 this_sequence A076544 A076545 A076546 %K A076543 easy,nonn %O A076543 0,2 %A A076543 Zak Seidov (zakseidov(AT)yahoo.com; zakseidov(AT)yahoo.com), Oct 19 2002 Search completed in 0.001 seconds