A178467 - OEIS

%I #19 Apr 11 2024 10:10:04

%S 0,3,6,9,28,30,18,35,32,36,50,66,72,91,154,120,96,187,144,190,100,147,

%T 176,184,288,275,208,270,224,261,180,248,288,297,442,420,324,407,342,

%U 390,320,410,462,473,660,630,506,611,528,588,450,561,624,636,864,825,672,798,696,767,480,610,682,693,960,910,726,871,748,828,560,710,792,803,1110,1050,836,1001,858,948,560,729,820,830,1176,1105,860,1044

%N a(n) = n * (number of letters in n in Italian).

%C a(0) and a(3) are the only terms such that a(k) = k^2.

%F a(n) = A001477(n)*A026858(n).

%e a(5)=30 since 5="cinque" has 6 letters in Italian and 5*6=30.

%e a(81)=729 since 81="ottantuno" has 9 letters.

%Y Cf. A001477, A026858.

%K nonn,word

%O 0,2

%A _Carmine Suriano_, Dec 23 2010

%E Edited by _N. J. A. Sloane_, Dec 23 2010

%E a(81) corrected by _Georg Fischer_, Apr 11 2024