A045558 Numbers whose factorial has '36' as its final two digits before the trailing zeros.

24, 63, 82, 95, 98, 104, 131, 163, 168, 172, 199, 213, 215, 234, 238, 241, 256, 284, 286, 291, 336, 343, 359, 363, 366, 408, 419, 445, 448, 504, 556, 564, 578, 617, 642, 671, 685, 693, 745, 748, 758, 769, 790

Offset

1,1

Links

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

Index entries for sequences related to final digits of numbers

Prog

(PARI) last(n, k)=if(n*8\9-1<k, n=n!; return(n/10^valuation(n, 10)%10^k)); my(m=Mod(1, 5^k)); for(i=2, n, m*=i/10^valuation(i, 5)); lift(chinese(m, Mod(0, 2^k))) \\ Gives the last k decimal digits of n!.
is(n)=last(n, 2)==36 \\ Charles R Greathouse IV, Oct 22 2014
(PARI) is(n)=my(m=Mod(1, 25)); for(i=2, n, m*=i/10^valuation(i, 5)); m==36 \\ Charles R Greathouse IV, Oct 22 2014
(PARI) v=List(); m=Mod(1, 25); for(n=2, 1e6, m*=n/10^valuation(n, 5); if(m==36, listput(v, n); if(#v==100, return(Vec(v))))) \\ Charles R Greathouse IV, Oct 22 2014

Crossrefs

Sequence in context: A226883 A304547 A371174 * A352343 A022761 A090386

Adjacent sequences: A045555 A045556 A045557 * A045559 A045560 A045561

Keyword

nonn,base

Author

Jeff Burch

Status

approved