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%I #16 Apr 29 2023 14:02:23
%S 2,4,16,46,196,946,8296,65246,385596,1568346,3925096,17165846,
%T 59491596,333414346,1000627096,1003689846,1013327596,1019992346,
%U 1099915096,1899135846,8291221596,65211444346,385412777096,1566619439846,3899692777596
%N Power each digit individually according to its position and add the numbers.
%C As the sequence tends to infinity the value of the least significant digit is always 6. The next digit is 4 or 9.
%e a(1) = 2.
%e a(2) = 2^2 = 4.
%e a(3) = 4^2 = 16.
%e a(4) = 1^2 *10 + 6^2 = 10 + 36 = 46.
%e a(5) = 4^2 *10 + 6^2 = 160 + 36 = 196.
%e a(6) = 1^2 *100 + 9^2 *10 + 6^2 = 100 + 810 +36 = 946.
%o (PARI) modN(n) = { local(resul,nshif,d) ; nshif = n; d = 0 ; resul = 0 ; while(nshif > 0, resul += 10^d* ((nshif % 10)^2) ; d++ ; nshif = floor(nshif/10) ; ) ; return(resul) ; }
%o { an=2 ; print(an,",") ; for (n = 2, 30, an=modN(an) ; print(an,",") ; ) } \\ _R. J. Mathar_, Mar 15 2006
%K nonn,base
%O 1,1
%A _Jorge Coveiro_, Dec 27 2005
%E More terms from _R. J. Mathar_, Mar 15 2006