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A254321 Hyper Wasteful numbers. 2
6, 8, 9, 22, 26, 30, 33, 34, 38, 40, 42, 44, 45, 48, 51, 52, 55, 56, 57, 60, 62, 63, 65, 66, 68, 70, 74, 75, 76, 77, 78, 80, 82, 84, 85, 86, 87, 88, 90, 91, 94, 95, 96, 99, 102, 110, 111, 112, 114, 115, 117, 118, 122, 130, 133, 136, 141, 144, 152, 153, 155, 161 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The distinction between the Wasteful numbers (A046760) is that the distinct digits are counted only instead all digits. Hence the definition:

Write n as product of primes raised to powers, let D(n) = total number of distinct digits in product representation (number of distinct digits in all the primes and number of distinct digits in all the exponents that are greater than 1) and nbd(n) = A043537(n) = number of distinct digits in n; sequence gives n such that D(n) > nbd(n).

LINKS

Table of n, a(n) for n=1..62.

EXAMPLE

88 is in the sequence because 88 = 2 ^ 3 * 11 => D(88)=3 > nbd(88)=1.

MATHEMATICA

Cases[Range[400], n_ /; Length[Union[Flatten[IntegerDigits[FactorInteger[n] /. 1 -> Sequence[]]]]] > Length[IntegerDigits[n]]]

PROG

(PARI) for(n=1, 100, s=[]; F=factor(n); for(i=1, #F[, 1], s=concat(s, digits(F[i, 1])); if(F[i, 2]>1, s=concat(s, digits(F[i, 2])))); if(#vecsort(digits(n), , 8)<#vecsort(s, , 8), print1(n, ", "))) \\ Derek Orr, Jan 30 2015

CROSSREFS

Cf. A043537, A046760, A046758, A046759, A254318, A254319.

Sequence in context: A092115 A083966 A074326 * A174213 A284990 A238621

Adjacent sequences:  A254318 A254319 A254320 * A254322 A254323 A254324

KEYWORD

nonn,base

AUTHOR

Michel Lagneau, Jan 28 2015

STATUS

approved

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Last modified August 11 06:25 EDT 2020. Contains 336422 sequences. (Running on oeis4.)