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A113904 Starting with 1, each number is the previous number plus the product of the index number and the sum of the digits of the previous number. 0

%I #6 Jun 25 2013 09:59:10

%S 1,2,6,24,48,108,162,225,297,459,639,837,1053,1170,1296,1566,1854,

%T 2160,2322,2493,2853,3231,3429,3843,4275,4725,5193,5679,6435,6957,

%U 7767,8604,9180,9774,10692,11322,11646,12312,12654,13356,14076,14814,15570,16344

%N Starting with 1, each number is the previous number plus the product of the index number and the sum of the digits of the previous number.

%F a(n) = a(n-1)+(n-1)*s(n-1), where s(n) stands for the sum of the digits of n.

%e a(6) = a(5)+ 5*s(a(5)) = 48+5*s(48) = 48+5*12 = 108

%t nxt[{n_,a_}]:={n+1,a+(n+1)Total[IntegerDigits[a]]}; Transpose[NestList[ nxt,{0,1},50]][[2]] (* _Harvey P. Dale_, Jun 25 2013 *)

%K base,easy,nonn

%O 1,2

%A Luc Stevens (lms022(AT)yahoo.com), Apr 20 2006

%E Corrected by _Harvey P. Dale_, Jun 25 2013

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