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A077350
Smallest number beginning with n and having exactly n divisors.
1
1, 2, 361, 46, 519885601, 63, 729, 88, 9025, 1053, 110462212541120451001, 126, 13841287201, 1458, 15376, 168, 1771091617586207101953855861006509233214261761, 180, 19267699140703639475173287301067237020969, 2000, 210681, 228352, 2384185791015625, 2430, 25091827216, 2625536, 27225, 28480
OFFSET
1,2
COMMENTS
Next (29th) term is 1039^28 and contains 85 digits. - Max Alekseyev, Feb 10 2005
EXAMPLE
a(6) = 63 = 3^2*7 has six divisors 1,3,7,9,21 and 63.
PROG
(PARI) { len10(n) = ceil(log(n+1)/log(10)); } { A077350(n) = if(isprime(n), forprime(i=2, 10^5, m=i^(n-1); if(m\10^(len10(m)-len10(n))==n, return(m))), for(d=0, 20, for(i=0, 10^d-1, m=n*10^d+i; if(numdiv(m)==n, return(m)))) ); return(0); } \\ Max Alekseyev
CROSSREFS
Sequence in context: A362476 A062381 A372992 * A013506 A013512 A295174
KEYWORD
base,nonn
AUTHOR
Amarnath Murthy, Nov 05 2002
EXTENSIONS
Corrected and extended by Max Alekseyev, Feb 10 2005
STATUS
approved