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A235680 The smallest first term of a sequence of n primes such that, after the first, each is equal to the previous prime plus the sum of all of its digits, plus the product of all of its nonzero digits. 1
2, 191, 163, 151, 127, 1644997, 36778597, 935715673, 50682890749, 16390560362269, 63334172492839 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The following term produced in each sequence after the n-th is necessarily a composite integer.

LINKS

Table of n, a(n) for n=1..11.

C. Rivera, Puzzle 727. Extending the OEIS sequence A235680

EXAMPLE

Example for n=8: a(8)=935715673 because after it the seven primes are 936311069, 936337351, 936490481, 936677149, 938391809, 938811763 and 939029537, with 936311069 = 935715673 + 9*3*5*7*1*5*6*7*3+(9+3+5+7+1+5+6+7+3) and so on...

CROSSREFS

Cf. A233692, A233783, A090009.

Sequence in context: A172801 A318195 A307587 * A085937 A142890 A201183

Adjacent sequences:  A235677 A235678 A235679 * A235681 A235682 A235683

KEYWORD

nonn,hard,more,base

AUTHOR

Carlos Rivera, Jan 13 2014

EXTENSIONS

a(9) from Giovanni Resta, Jan 13 2014

a(10)-a(11) from Giovanni Resta, Feb 22 2014

STATUS

approved

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Last modified June 18 17:51 EDT 2021. Contains 345120 sequences. (Running on oeis4.)