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 A124436 a(1)=1, a(n)=p_i^d_i where p_i is i-th prime and d_i is i-th digit of a(n-1). 0
 1, 2, 4, 16, 1458, 2918430506250, 7164640537512654203797788776525821310188011060 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Or a(n-1)= decimal encoding of the prime factorization of a(n). Cf. A068633 Let n = p^a*q^b... then a(n) = concatenation paqb..., A067599 Decimal encoding of the prime factorization of n. LINKS EXAMPLE a(4)=16, a(5)=2^1 * 3^6 = 1458; a(6)= 2^1 * 3^4 * 5^5 * 7^8 = 2918430506250. MATHEMATICA a[1]=1; id[n_]:=id[n]=IntegerDigits[a[n-1]]; a[n_]:=a[n]= Times@@Table[Prime[i]^id[n][[i]], {i, 1, Length[id[n]]}]; {1, Table[a[n], {n, 2, 7}]}//Flatten CROSSREFS Cf. A067599, A068633. Sequence in context: A194457 A001128 A280890 * A014221 A249760 A271552 Adjacent sequences:  A124433 A124434 A124435 * A124437 A124438 A124439 KEYWORD base,nonn AUTHOR Zak Seidov, Dec 16 2006 STATUS approved

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Last modified October 16 15:51 EDT 2019. Contains 328101 sequences. (Running on oeis4.)