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A242589 Primes p such that p = the cumulative sum of the digit-sum in base 15 of the digit-product in base 4 of each prime < p. 0

%I

%S 5,19,37,43,97,107,6091,6389,7121,21727,147107,148151,148279,148429,

%T 148469,172877,173209,173741,2621387,5642293,5642321,8932771,8981827,

%U 8981879,9094979,9095089,9997783,10010687,10010789,10037749,10144523,40179929,40365217,40379077,40379197,40386811,40612933

%N Primes p such that p = the cumulative sum of the digit-sum in base 15 of the digit-product in base 4 of each prime < p.

%F sum = sum + digit-sum(digit-mult(prime,base=4),base=15). The function digit-mult(n) multiplies all digits d of n, where d > 0. For example, digit-mult(1230) = 1 * 2 * 3 = 6. Therefore, the digit-sum in base 15 of the digit-mult(333) in base 4 = digit-sum(3 * 3 * 3) = digit-sum(1C) = 1 + C = 13. (1C in base 15 = 27 in base 10).

%e 5 = digit-sum(digit-mult(2,b=4),b=15) + sum(mult(3,b=4),b=15) = 2 + 3.

%e 19 = digit-sum(digit-mult(2,b=4),b=15) + sum(mult(3,b=4),b=15) + sum(mult(11,b=4),b=15) + sum(mult(13,b=4),b=15) + sum(mult(23,b=4),b=15) + sum(mult(31,b=4),b=15) + sum(mult(101,b=4),b=15) = 2 + 3 + 1 + 3 + 6 + 3 + 1.

%Y Cf. A240886 (similar sequence with digit sums in base 3).

%K nonn,base

%O 1,1

%A _Anthony Sand_, May 20 2014

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Last modified December 1 05:02 EST 2022. Contains 358454 sequences. (Running on oeis4.)